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meso-reference

Section: Misc. Reference Manual Pages (3)
Updated: 202-0-15
Index Return to Main Contents

---

 

NAME

meso-reference v1.10.2- a reference for meson functions and objects  

DESCRIPTION

This manual is divided into two sections, FUNCTIONS and OBJECTS. FUNCTIONS contains a reference for all meson functions and methods. Methods are denoted by object_name.method_name(). OBJECTS contains additional information about each object.  

FUNCTIONS

 

add_global_arguments()

SYNOPSIS

void add_global_arguments(

Compiler argument...,
language:,
native: false,

)

DESCRIPTION

Adds global arguments to the compiler command line.

VARARGS

Compiler argument str, 0...N times

The compiler arguments to add

KWARGS

language array[str], required

Specifies the language(s) that the arguments should be applied to. If an array of languages is given, the arguments are added to each of the corresponding compiler command lines. Note that there is no way to remove an argument set in this way. If you have an argument that is only used in a subset of targets, you have to specify it in pe-target flags.

native bool, default: false, since 0.48.0

A boolean specifying whether the arguments should be applied to the native or cross compilation. If `true` the arguments will only be used for native compilations. If `false` the arguments will only be used in cross compilations. If omitted, the flags are added to native compilations if compiling natively and cross compilations (only) when cross compiling.

NOTES

Usually you should use add_project_arguments instead, because that works even when you project is used as a subproject. You must pass always arguments individually `arg1, arg2, ...` rather than as a string `'arg1 arg2', ...`

 

add_global_link_arguments()

SYNOPSIS

void add_global_link_arguments(

Linker argument...,
language:,
native: false,

)

DESCRIPTION

Adds global arguments to the linker command line.

Like add_global_arguments but the arguments are passed to the linker.

VARARGS

Linker argument str, 0...N times

The linker arguments to add

KWARGS

language array[str], required

Specifies the language(s) that the arguments should be applied to. If an array of languages is given, the arguments are added to each of the corresponding compiler command lines. Note that there is no way to remove an argument set in this way. If you have an argument that is only used in a subset of targets, you have to specify it in pe-target flags.

native bool, default: false, since 0.48.0

A boolean specifying whether the arguments should be applied to the native or cross compilation. If `true` the arguments will only be used for native compilations. If `false` the arguments will only be used in cross compilations. If omitted, the flags are added to native compilations if compiling natively and cross compilations (only) when cross compiling.

NOTES

Usually you should use add_project_link_arguments instead, because that works even when you project is used as a subproject. You must pass always arguments individually `arg1, arg2, ...` rather than as a string `'arg1 arg2', ...`

 

add_languages()

SYNOPSIS

bool add_languages(Language..., native:, required: true)

DESCRIPTION

Add programming languages used by the project.

This is equivalent to having them in the `project` declaration. This function is usually used to add languages that are only used under some conditions.

Returns `true` if all languages specified were found and `false` otherwise.

If `native` is omitted, the languages may be used for either build or host machine, but are never required for the build machine. (i.e. it is equivalent to `add_languages(langs, native: false, required: required) and add_languages(langs, native: true, required: false)`. This default behaviour may change to `native: false` in a future Meson version.

VARARGS

Language str, 0...N times

The languages to add

KWARGS

native bool, since 0.54.0

If set to `true`, the language will be used to compile for the build machine, if `false`, for the host machine.

required bool | feature, default: true

If set to `true`, Meson will halt if any of the languages specified are not found. (since 0.47.0) The value of a `feature`[1] option can also be passed.

EXAMPLE

project('foobar', 'c')

if compiling_for_osx

  add_languages('objc')
endif
if add_languages('cpp', required : false)

  executable('cp-app', 'main.cpp')
endif

# More code...

 

add_project_arguments()

SYNOPSIS

void add_project_arguments(

Compiler argument...,
language:,
native: false,

)

DESCRIPTION

Adds project specific arguments to the compiler command line.

This function behaves in the same way as add_global_arguments except that the arguments are only used for the current project, they won't be used in any other subproject.

VARARGS

Compiler argument str, 0...N times

The compiler arguments to add

KWARGS

language array[str], required

Specifies the language(s) that the arguments should be applied to. If an array of languages is given, the arguments are added to each of the corresponding compiler command lines. Note that there is no way to remove an argument set in this way. If you have an argument that is only used in a subset of targets, you have to specify it in pe-target flags.

native bool, default: false, since 0.48.0

A boolean specifying whether the arguments should be applied to the native or cross compilation. If `true` the arguments will only be used for native compilations. If `false` the arguments will only be used in cross compilations. If omitted, the flags are added to native compilations if compiling natively and cross compilations (only) when cross compiling.

NOTES

You must pass always arguments individually `arg1, arg2, ...` rather than as a string `'arg1 arg2', ...`

 

add_project_dependencies()

SYNOPSIS

void add_project_dependencies(

dependencies...,
language:,
native: false,

)

since 0.63.0

DESCRIPTION

Adds arguments to the compiler and linker command line, so that the given set of dependencies is included in all build products for this project.

VARARGS

dependencies dep, 0...N times

The dependencies to add; if internal dependencies are included, they must not include any built object.

KWARGS

language array[str], required

Specifies the language(s) that the arguments should be applied to. If an array of languages is given, the arguments are added to each of the corresponding compiler command lines. Note that there is no way to remove an argument set in this way. If you have an argument that is only used in a subset of targets, you have to specify it in pe-target flags.

native bool, default: false, since 0.48.0

A boolean specifying whether the arguments should be applied to the native or cross compilation. If `true` the arguments will only be used for native compilations. If `false` the arguments will only be used in cross compilations. If omitted, the flags are added to native compilations if compiling natively and cross compilations (only) when cross compiling.

 

add_project_link_arguments()

SYNOPSIS

void add_project_link_arguments(

Linker argument...,
language:,
native: false,

)

DESCRIPTION

Adds project specific arguments to the linker command line.

Like add_project_arguments but the arguments are passed to the linker.

VARARGS

Linker argument str, 0...N times

The linker arguments to add

KWARGS

language array[str], required

Specifies the language(s) that the arguments should be applied to. If an array of languages is given, the arguments are added to each of the corresponding compiler command lines. Note that there is no way to remove an argument set in this way. If you have an argument that is only used in a subset of targets, you have to specify it in pe-target flags.

native bool, default: false, since 0.48.0

A boolean specifying whether the arguments should be applied to the native or cross compilation. If `true` the arguments will only be used for native compilations. If `false` the arguments will only be used in cross compilations. If omitted, the flags are added to native compilations if compiling natively and cross compilations (only) when cross compiling.

NOTES

You must pass always arguments individually `arg1, arg2, ...` rather than as a string `'arg1 arg2', ...`

 

add_test_setup()

SYNOPSIS

void add_test_setup(

name,
env:,
exclude_suites:,
exe_wrapper:,
gdb: false,
is_default: false,
timeout_multiplier: 1,

)

DESCRIPTION

Add a custom test setup. This setup can be used to run the tests with a custom setup, for example under Valgrind.

To use the test setup, run `meson test-setup=name` inside the build dir.

Note that all these options are also available while running the `meson test` script for running tests instead of `ninja test` or `msbuild RUN_TESTS.vcxproj`, etc depending on the backend.

POSARGS

name str, required

The name of the test setup

KWARGS

env env | array[str] | dict[str]

environment variables to set , such as `['NAME1=value1', 'NAME2=value2']`, or an env object which allows more sophisticated environment juggling. (Since 0.52.0) A dictionary is also accepted.

exclude_suites array[str], since 0.57.0

An array of test suites that should be excluded when using this setup. Suites specified in the -suite` option to `meson test` will always run, overriding `add_test_setup` if necessary.

exe_wrapper array[str | external_program]

The command or script followed by the arguments to it

gdb bool, default: false

If `true`, the tests are also run under `gdb`

is_default bool, default: false, since 0.49.0

Set whether this is the default test setup. If `true`, the setup will be used whenever `meson test` is run without the -setup` option.

timeout_multiplier int, default: 1

A number to multiply the test timeout with. Since 0.57 if timeout_multiplier is `<= 0` the test has infinite duration, in previous versions of Meson the test would fail with a timeout immediately.

 

alias_target()

SYNOPSIS

alias_tgt alias_target(target_name, Dep...)

since 0.52.0

DESCRIPTION

This function creates a new to-level target. Like all to-level targets, this integrates with the selected backend. For instance, with you can run it as `meson compile target_name`. This is a dummy target that does not execute any command, but ensures that all dependencies are built. Dependencies can be any build target. Since 0.60.0, this includes run_tgt.

Since 1.6.0 passing a both_libs object builds both shared and static libraries.

POSARGS

target_name str, required

The name of the alias target

VARARGS

Dep tgt, 1...N times

The targets to depend on

 

assert()

SYNOPSIS

void assert(condition, [message])

DESCRIPTION

Abort with an error message if `condition` evaluates to `false`.

POSARGS

condition bool, required

Abort if this evaluates to `false`

OPTARGS

message str

The error message to print.

NOTES

The `message` argument is optional since 0.53.0 and defaults to print the condition statement.

 

benchmark()

SYNOPSIS

void benchmark(

name,
executable,
args:,
depends:,
env:,
priority: 0,
protocol: 'exitcode',
should_fail: false,
suite:,
timeout: 30,
verbose: false,
workdir:,

)

DESCRIPTION

Creates a benchmark item that will be run when the benchmark target is run. The behavior of this function is identical to test except for:

* benchmark() has no `is_parallel` keyword because benchmarks are not run in parallel
* benchmark() does not automatically add the `MALLOC_PERTURB_` environment variable

Defined benchmarks can be run in a backen-agnostic way by calling `meson test-benchmark` inside the build dir, or by using backen-specific commands, such as `ninja benchmark` or `msbuild RUN_TESTS.vcxproj`.

POSARGS

name str, required

The unique test id

executable exe | jar | external_program | file | custom_tgt | custom_idx, required

The program to execute. (Since 1.4.0) A CustomTarget is also accepted.

KWARGS

args array[str | file | tgt | external_program]

Arguments to pass to the executable

depends array[build_tgt | custom_tgt], since 0.46.0

specifies that this test depends on the specified target(s), even though it does not take any of them as a command line argument. This is meant for cases where test finds those targets internally, e.g. plugins or globbing. Those targets are built before test is executed even if they have `build_by_default : false`.

env env | array[str] | dict[str]

environment variables to set, such as `['NAME1=value1', 'NAME2=value2']`, or an env object which allows more sophisticated environment juggling. (Since 0.52.0) A dictionary is also accepted.

priority int, default: 0, since 0.52.0

specifies the priority of a test. Tests with a higher priority are started before tests with a lower priority. The starting order of tests with identical priorities is implementatio-defined. The default priority is 0, negative numbers are permitted.

protocol str, default: 'exitcode', since 0.50.0

specifies how the test results are parsed and can be one of `exitcode`, `tap`, or `gtest`. For more information about test harness protocol read Unit Tests[2]. The following values are accepted:

- `exitcode`: the executable's exit code is used by the test harness to record the outcome of the test).
- `tap`: Test Anything Protocol[3].
- `gtest` (since 0.55.0): for Google Tests.
- `rust` (since 0.56.0): for native rust tests

should_fail bool, default: false

when true the test is considered passed if the executable returns a no-zero return value (i.e. reports an error)

suite str | array[str]

`'label'` (or array of labels `['label1', 'label2']`) attached to this test. The suite name is qualified by a (sub)project name resulting in `(sub)project_name:label`. In the case of an array of strings, the suite names will be `(sub)project_name:label1`, `(sub)project_name:label2`, etc.

timeout int, default: 30

the amount of seconds the test is allowed to run, a test that exceeds its time limit is always considered failed, defaults to 30 seconds. Since 0.57 if timeout is `<= 0` the test has infinite duration, in previous versions of Meson the test would fail with a timeout immediately.

verbose bool, default: false, since 0.62.0

if true, forces the test results to be logged as if -verbose` was passed to `meson test`.

workdir str

absolute path that will be used as the working directory for the test

NOTES

Prior to 0.52.0 benchmark would warn that `depends` and `priority` were unsupported, this is incorrect.

 

both_libraries()

SYNOPSIS

both_libs both_libraries(

target_name,
source...,
<lang>_args:,
<lang>_pch:,
<lang>_shared_args:,
<lang>_static_args:,
build_by_default: true,
build_rpath:,
build_subdir:,
d_debug:,
d_import_dirs:,
d_module_versions:,
d_unittest: false,
darwin_versions:,
dependencies:,
extra_files:,
gnu_symbol_visibility:,
gui_app: false,
implicit_include_directories: true,
include_directories:,
install: false,
install_dir:,
install_mode:,
install_rpath:,
install_tag:,
link_args:,
link_depends:,
link_language:,
link_whole:,
link_with:,
name_prefix:,
name_suffix:,
native: false,
objects:,
override_options:,
pic:,
prelink:,
rust_abi:,
rust_crate_type:,
rust_dependency_map:,
shortname:,
sources:,
soversion:,
vala_args:,
vala_gir:,
vala_header:,
vala_shared_args:,
vala_static_args:,
vala_vapi:,
version:,
vs_module_defs:,
win_subsystem: 'console',

)

since 0.46.0

DESCRIPTION

Builds both a static and shared library with the given sources. Positional and keyword arguments are otherwise the same as for library. Source files will be compiled only once and object files will be reused to build both shared and static libraries, unless `b_staticpic` user option or `pic` argument are set to false in which case sources will be compiled twice.

POSARGS

target_name str, required

The unique name of the build target

VARARGS

source str | file | custom_tgt | custom_idx | generated_list, 0...N times

Input source to compile. The following types are supported:

- Strings relative to the current source directory
- file objects defined in any preceding build file
- The return value of configur-time generators such as configure_file
- The return value of buil-time generators such as custom_target or generator.process

These input files can be sources, objects, libraries, or any other file. Meson will automatically categorize them based on the extension and use them accordingly. For instance, sources (`.c`, `.cpp`, `.vala`, `.rs`, etc) will be compiled and objects (`.o`, `.obj`) and libraries (`.so`, `.dll`, etc) will be linked.

With the Ninja backend, Meson will create a buil-time orde-only dependency[4] on all generated input files, including unknown files. This is needed to bootstrap the generation of the real dependencies in the depfile[5] generated by your compiler to determine when to rebuild sources. Ninja relies on this dependency file for all input files, generated and no-generated. The behavior is similar for other backends.

KWARGS

<lang>_args array[str]

compiler flags to use for the given language; eg: `cpp_args` for C++

<lang>_pch str

precompiled header file to use for the given language

<lang>_shared_args array[str], since 1.3.0

Arguments that are only passed to a shared library

<lang>_static_args array[str], since 1.3.0

Arguments that are only passed to a static library

build_by_default bool, default: true, since 0.38.0

Causes, when set to `true`, to have this target be built by default. This means it will be built when `meson compile` is called without any arguments. The default value is `true` for all built target types.

build_rpath str, since 0.42.0

A string to add to target's rpath definition in the build dir, but which will be removed on install

build_subdir str, since 1.10.0

Places the build results in a subdirectory of the given name rather than directly into the build directory. This does not affect the install directory, which uses install_dir. This allows inserting a directory name into the build path, either when needed to use the build result while building other targets or as a way to support multiple targets with the same basename by using unique build_subdir values for each one. To prevent collisions within the build directory, build_subdir is not allowed to match a file or directory in the source directory, nor contain '..' to refer to the parent of the build directory.

d_debug array[str]

The D version identifiers[6] to add during the compilation of D source files.

d_import_dirs array[inc | str], since 0.62.0

the directories to add to the string search path (i.e. -J` switch for DMD). Must be inc objects or plain strings.

d_module_versions array[str | int]

List of module version identifiers set when compiling D sources.

d_unittest bool, default: false

When set to true, the D modules are compiled in debug mode.

darwin_versions str | int | array[str], since 0.48.0

Defines the `compatibility version` and `current version` for the dylib on macOS. If an array is specified, it must be either zero, one, or two elements. If only one element is specified or if it's not an array the specified value will be used for setting both compatibility version and current version. If unspecified, the `soversion` will be used as per the aforementioned rules.

dependencies array[dep]

one or more dependency objects created with dependency or compiler.find_library (for external deps) or declare_dependency (for deps built by the project)

extra_files str | file

Not used for the build itself but are shown as source files in IDEs that group files by targets (such as Visual Studio).

These may only be static sources.

gnu_symbol_visibility str, since 0.48.0

Specifies how symbols should be exported, see e.g the GCC Wiki[7] for more information. This value can either be an empty string or one of `default`, `internal`, `hidden`, `protected` or `inlineshidden`, which is the same as `hidden` but also includes things like C++ implicit constructors as specified in the GCC manual. Ignored on compilers that do not support GNU visibility arguments. See also `snippets.symbol_visibility_header()`[8] method to help with defining public API.

gui_app bool, default: false, deprecated since 0.56.0

When set to true flags this target as a GUI application on platforms where this makes a difference, deprecated since 0.56.0, use `win_subsystem` instead.

implicit_include_directories bool, default: true, since 0.42.0

Controls whether Meson adds the current source and build directories to the include path

include_directories array[inc | str]

one or more objects created with the include_directories function, or (since 0.50.0) strings, which will be transparently expanded to include directory objects

install bool, default: false

When set to true, this executable should be installed.

install_dir str

override install directory for this file. If the value is a relative path, it will be considered relative the `prefix` option. For example, if you want to install plugins into a subdir, you'd use something like this: `install_dir : get_option('libdir') / 'projectnam-1.0'`.

install_mode array[str | int], since 0.47.0

Specify the file mode in symbolic format and optionally the owner/uid and group/gid for the installed files.

See the `install_mode` kwarg of install_data for more information.

install_rpath str

A string to set the target's rpath to after install (but not before that). On Windows, this argument has no effect.

install_tag str, since 0.60.0

A string used by the `meson install-tags` command to install only a subset of the files. By default all build targets have the tag `runtime` except for static libraries that have the `devel` tag.

link_args array[str]

Flags to use during linking. You can use UNI-style flags here for all platforms.

link_depends str | file | custom_tgt | custom_idx

Strings, files, or custom targets the link step depends on such as a symbol visibility map. The purpose is to automatically trigger a r-link (but not a r-compile) of the target when this file changes.

link_language str, since 0.51.0

Makes the linker for this target be for the specified language. It is generally unnecessary to set this, as Meson will detect the right linker to use in most cases. There are only two cases where this is needed. One, your main function in an executable is not in the language Meson picked, or second you want to force a library to use only one ABI.

(broken until 0.55.0)

link_whole array[lib | custom_tgt | custom_idx], since 0.40.0

Links all contents of the given static libraries whether they are used or not, equivalent to the -Wl-whol-archive` argument flag of GCC, or the '/WHOLEARCHIVE' MSVC linker option. This allows the linked target to r-export symbols from all objects in the static libraries.

(since 0.41.0) If passed an array that array will be flattened.

(since 0.51.0) This argument also accepts outputs produced by custom targets. The user must ensure that the output is a library in the correct format.

link_with array[lib | custom_tgt | custom_idx]

One or more shared or static libraries (built by this project) that this target should be linked with. (since 0.41.0) If passed an array that array will be flattened. (since 0.51.0) The arguments can also be custom targets. In this case Meson will assume that merely adding the output file in the linker command line is sufficient to make linking work. If this is not sufficient, then the build system writer must write all other steps manually.

name_prefix str | array[void]

The string that will be used as the prefix for the target output filename by overriding the default (only used for libraries). By default this is `lib` on all platforms and compilers, except for MSVC shared libraries where it is omitted to follow convention, and Cygwin shared libraries where it is `cyg`.

Set this to `[]`, or omit the keyword argument for the default behaviour.

name_suffix str | array[void]

The string that will be used as the extension for the target by overriding the default. By default on Windows this is `exe` for executables and on other platforms it is omitted.

For shared libraries, the default value is `dylib` on macOS, `dll` on Windows, and `so` everywhere else. For static libraries, it is `a` everywhere. By convention MSVC static libraries use the `lib` suffix, but we use `a` to avoid a potential name clash with shared libraries which also generate import libraries with a `lib` suffix.

Set this to `[]`, or omit the keyword argument for the default behaviour.

native bool, default: false

Controls whether the target is compiled for the build or host machines.

objects array[extracted_obj | file | str]

List of object files that should be linked in this target.

Since 1.1.0 this can include generated files in addition to object files that you don't have source to or that object files produced by other build targets. In earlier release, generated object files had to be placed in `sources`.

override_options array[str] | dict[str | bool | int | array[str]], since 0.40.0

takes an array of strings in the same format as `project`'s `default_options` overriding the values of these options for this target only. (since 1.2.0): A dictionary may now be passed.

pic bool, since 0.36.0

Builds the library as positional independent code (so it can be linked into a shared library). This option has no effect on Windows and OS X since it doesn't make sense on Windows and PIC cannot be disabled on OS X.

prelink bool, since 0.57.0

If `true` the object files in the target will be prelinked, meaning that it will contain only one prelinked object file rather than the individual object files.

rust_abi str, since 1.3.0

Set the specific ABI to compile (when compiling rust).- 'rust' (default): Create a "rlib" or "dylib" crate depending on the library type being build.
- 'c': Create a "cdylib" or "staticlib" crate depending on the library type being build.

rust_crate_type str, deprecated since 1.3.0, since 0.42.0

Set the specific type of rust crate to compile (when compiling rust).

If the target is an executable this defaults to "bin", the only allowed value.

If it is a static_library it defaults to "lib", and may be "lib", "staticlib", or "rlib". If "lib" then Rustc will pick a default, "staticlib" means a C ABI library, "rlib" means a Rust ABI.

If it is a shared_library it defaults to "lib", and may be "lib", "dylib", "cdylib", or "pro-macro". If "lib" then Rustc will pick a default, "cdylib" means a C ABI library, "dylib" means a Rust ABI, and "pro-macro" is a special rust procedural macro crate.

"pro-macro" is new in 0.62.0.

Since 1.3.0 this is deprecated and replaced by "rust_abi" keyword argument. `proc_macro` crates are now handled by the `rust.proc_macro()`[9] method.

rust_dependency_map dict[str], since 1.2.0

On rust targets this allows giving custom names to the crates that are linked into the target. For example, passing a dependency map of `{ 'gtk4': 'gtk' }` has the same effect of writing `gtk.package = "gtk4"` in the `dependencies` section of a Cargo.toml file, or `extern crate gtk4 as gtk` inside Rust code.

Since 1.10.0, the keys can be either crate names or target names.

shortname str, since 1.10.0

A string specifying a DLL name fitting to 8.3 limit on OS/2 of this shared library.

sources str | file | custom_tgt | custom_idx | generated_list | structured_src

Additional source files. Same as the source varargs.

soversion str | int

A string or integer specifying the soversion of this shared library, such as `0`. On Linux and Windows this is used to set the soversion (or equivalent) in the filename. For example, if `soversion` is `4`, a Windows DLL will be called `fo-4.dll` and one of the aliases of the Linux shared library would be `libfoo.so.4`. If this is not specified, the first part of `version` is used instead (see below). For example, if `version` is `3.6.0` and `soversion` is not defined, it is set to `3`.

vala_args array[str | file]

Compiler flags for Vala. Unlike other languages this may contain Files

vala_gir str

If set, generates a GIR file with the given name. If this is unset then no GIR file will be generated.

vala_header str

On Vala targets, this provides a way to override the name of the generated C compatible header for targets that generate them.

If it is not set the default will be calculated from the target's name.

vala_shared_args array[str | file], since 1.3.0

Arguments that are only passed to a shared library Like `vala_args`, files is allowed in addition to string

vala_static_args array[str | file], since 1.3.0

Arguments that are only passed to a static library Like `vala_args`, files is allowed in addition to string

vala_vapi str

On Vala targets, this provides a way to override the name of the generated VAPI file.

If it is not set the default will be calculated from the target's name.

version str

A string specifying the version of this shared library, such as `1.1.0`. On Linux and OS X, this is used to set the shared library version in the filename, such as `libfoo.so.1.1.0` and `libfoo.1.1.0.dylib`. If this is not specified, `soversion` is used instead (see above).

vs_module_defs str | file | custom_tgt | custom_idx

Specify a Microsoft module definition file for controlling symbol exports, etc., on platforms where that is possible (e.g. Windows).

(Since 1.3.0) custom_idx are supported

win_subsystem str, default: 'console', since 0.56.0

Specifies the subsystem type to use on the Windows platform. Typical values include `console` for text mode programs and `windows` for gui apps. The value can also contain version specification such as `windows,6.0`. See MSDN documentation[10] for the full list.

 

build_target()

SYNOPSIS

build_tgt build_target(

target_name,
source...,
<lang>_args:,
<lang>_pch:,
<lang>_shared_args:,
<lang>_static_args:,
android_exe_type: 'executable',
build_by_default: true,
build_rpath:,
build_subdir:,
d_debug:,
d_import_dirs:,
d_module_versions:,
d_unittest: false,
darwin_versions:,
dependencies:,
export_dynamic:,
extra_files:,
gnu_symbol_visibility:,
gui_app: false,
implib:,
implicit_include_directories: true,
include_directories:,
install: false,
install_dir:,
install_mode:,
install_rpath:,
install_tag:,
java_resources:,
link_args:,
link_depends:,
link_language:,
link_whole:,
link_with:,
main_class:,
name_prefix:,
name_suffix:,
native: false,
objects:,
override_options:,
pic:,
pie:,
prelink:,
rust_abi:,
rust_crate_type:,
rust_dependency_map:,
shortname:,
sources:,
soversion:,
target_type:,
vala_args:,
vala_gir:,
vala_header:,
vala_shared_args:,
vala_static_args:,
vala_vapi:,
version:,
vs_module_defs:,
win_subsystem: 'console',

)

DESCRIPTION

Creates a build target whose type can be set dynamically with the `target_type` keyword argument.

`target_type` may be set to one of:

- `executable` (see executable)
- `shared_library` (see shared_library)
- `shared_module` (see shared_module)
- `static_library` (see static_library)
- `both_libraries` (see both_libraries)
- `library` (see library)
- `jar` (see jar)*

This declaration:

executable(<arguments and keyword arguments>)

is equivalent to this:

build_target(<arguments and keyword arguments>, target_type : 'executable')

The arrays for the kwargs (such as `sources`, `objects`, and `dependencies`) are always flattened, which means you can freely nest and add arrays while creating the final array.

The returned object also has methods that are documented in build_tgt.

*"jar" is deprecated because it is fundamentally a different thing than the other build_target types.

POSARGS

target_name str, required

The unique name of the build target

VARARGS

source str | file | custom_tgt | custom_idx | generated_list, 0...N times

Input source to compile. The following types are supported:

- Strings relative to the current source directory
- file objects defined in any preceding build file
- The return value of configur-time generators such as configure_file
- The return value of buil-time generators such as custom_target or generator.process

These input files can be sources, objects, libraries, or any other file. Meson will automatically categorize them based on the extension and use them accordingly. For instance, sources (`.c`, `.cpp`, `.vala`, `.rs`, etc) will be compiled and objects (`.o`, `.obj`) and libraries (`.so`, `.dll`, etc) will be linked.

With the Ninja backend, Meson will create a buil-time orde-only dependency[3] on all generated input files, including unknown files. This is needed to bootstrap the generation of the real dependencies in the depfile[4] generated by your compiler to determine when to rebuild sources. Ninja relies on this dependency file for all input files, generated and no-generated. The behavior is similar for other backends.

KWARGS

<lang>_args array[str]

compiler flags to use for the given language; eg: `cpp_args` for C++

<lang>_pch str

precompiled header file to use for the given language

<lang>_shared_args array[str], since 1.3.0

Arguments that are only passed to a shared library

<lang>_static_args array[str], since 1.3.0

Arguments that are only passed to a static library

android_exe_type str, default: 'executable', since 1.8.0

Specifies the intended target of the executable. This can either be `executable`, if the intended usecase is to run the executable using fork + exec, or `application` if the executable is supposed to be loaded as shared object by the android runtime.

build_by_default bool, default: true, since 0.38.0

Causes, when set to `true`, to have this target be built by default. This means it will be built when `meson compile` is called without any arguments. The default value is `true` for all built target types.

build_rpath str, since 0.42.0

A string to add to target's rpath definition in the build dir, but which will be removed on install

build_subdir str, since 1.10.0

Places the build results in a subdirectory of the given name rather than directly into the build directory. This does not affect the install directory, which uses install_dir. This allows inserting a directory name into the build path, either when needed to use the build result while building other targets or as a way to support multiple targets with the same basename by using unique build_subdir values for each one. To prevent collisions within the build directory, build_subdir is not allowed to match a file or directory in the source directory, nor contain '..' to refer to the parent of the build directory.

d_debug array[str]

The D version identifiers[5] to add during the compilation of D source files.

d_import_dirs array[inc | str], since 0.62.0

the directories to add to the string search path (i.e. -J` switch for DMD). Must be inc objects or plain strings.

d_module_versions array[str | int]

List of module version identifiers set when compiling D sources.

d_unittest bool, default: false

When set to true, the D modules are compiled in debug mode.

darwin_versions str | int | array[str], since 0.48.0

Defines the `compatibility version` and `current version` for the dylib on macOS. If an array is specified, it must be either zero, one, or two elements. If only one element is specified or if it's not an array the specified value will be used for setting both compatibility version and current version. If unspecified, the `soversion` will be used as per the aforementioned rules.

dependencies array[dep]

one or more dependency objects created with dependency or compiler.find_library (for external deps) or declare_dependency (for deps built by the project)

export_dynamic bool, since 0.45.0

when set to true causes the target's symbols to be dynamically exported, allowing modules built using the shared_module function to refer to functions, variables and other symbols defined in the executable itself.

extra_files str | file

Not used for the build itself but are shown as source files in IDEs that group files by targets (such as Visual Studio).

These may only be static sources.

gnu_symbol_visibility str, since 0.48.0

Specifies how symbols should be exported, see e.g the GCC Wiki[6] for more information. This value can either be an empty string or one of `default`, `internal`, `hidden`, `protected` or `inlineshidden`, which is the same as `hidden` but also includes things like C++ implicit constructors as specified in the GCC manual. Ignored on compilers that do not support GNU visibility arguments. See also `snippets.symbol_visibility_header()`[7] method to help with defining public API.

gui_app bool, default: false, deprecated since 0.56.0

When set to true flags this target as a GUI application on platforms where this makes a difference, deprecated since 0.56.0, use `win_subsystem` instead.

implib bool | str, since 0.42.0

When set to a string, that will be the name of a generated import library.

Since 1.10.0 passing a boolean value is deprecated.

When set to true, an import library is generated for the executable (the name of the import library is based on exe_name). Alternatively, when set to a string, that gives the base name for the import library. The import library is used when the returned build target object appears in `link_with:` elsewhere. Only has any effect on platforms where that is meaningful (e.g. Windows). Implies the `export_dynamic` argument.

implicit_include_directories bool, default: true, since 0.42.0

Controls whether Meson adds the current source and build directories to the include path

include_directories array[inc | str]

one or more objects created with the include_directories function, or (since 0.50.0) strings, which will be transparently expanded to include directory objects

install bool, default: false

When set to true, this executable should be installed.

install_dir str

override install directory for this file. If the value is a relative path, it will be considered relative the `prefix` option. For example, if you want to install plugins into a subdir, you'd use something like this: `install_dir : get_option('libdir') / 'projectnam-1.0'`.

install_mode array[str | int], since 0.47.0

Specify the file mode in symbolic format and optionally the owner/uid and group/gid for the installed files.

See the `install_mode` kwarg of install_data for more information.

install_rpath str

A string to set the target's rpath to after install (but not before that). On Windows, this argument has no effect.

install_tag str, since 0.60.0

A string used by the `meson install-tags` command to install only a subset of the files. By default all build targets have the tag `runtime` except for static libraries that have the `devel` tag.

java_resources structured_src, since 0.62.0

Resources to be added to the jar

link_args array[str]

Flags to use during linking. You can use UNI-style flags here for all platforms.

link_depends str | file | custom_tgt | custom_idx

Strings, files, or custom targets the link step depends on such as a symbol visibility map. The purpose is to automatically trigger a r-link (but not a r-compile) of the target when this file changes.

link_language str, since 0.51.0

Makes the linker for this target be for the specified language. It is generally unnecessary to set this, as Meson will detect the right linker to use in most cases. There are only two cases where this is needed. One, your main function in an executable is not in the language Meson picked, or second you want to force a library to use only one ABI.

(broken until 0.55.0)

link_whole array[lib | custom_tgt | custom_idx], since 0.40.0

Links all contents of the given static libraries whether they are used or not, equivalent to the -Wl-whol-archive` argument flag of GCC, or the '/WHOLEARCHIVE' MSVC linker option. This allows the linked target to r-export symbols from all objects in the static libraries.

(since 0.41.0) If passed an array that array will be flattened.

(since 0.51.0) This argument also accepts outputs produced by custom targets. The user must ensure that the output is a library in the correct format.

link_with array[lib | custom_tgt | custom_idx]

One or more shared or static libraries (built by this project) that this target should be linked with. (since 0.41.0) If passed an array that array will be flattened. (since 0.51.0) The arguments can also be custom targets. In this case Meson will assume that merely adding the output file in the linker command line is sufficient to make linking work. If this is not sufficient, then the build system writer must write all other steps manually.

main_class str

Main class for running the built jar

name_prefix str | array[void]

The string that will be used as the prefix for the target output filename by overriding the default (only used for libraries). By default this is `lib` on all platforms and compilers, except for MSVC shared libraries where it is omitted to follow convention, and Cygwin shared libraries where it is `cyg`.

Set this to `[]`, or omit the keyword argument for the default behaviour.

name_suffix str | array[void]

The string that will be used as the extension for the target by overriding the default. By default on Windows this is `exe` for executables and on other platforms it is omitted.

For shared libraries, the default value is `dylib` on macOS, `dll` on Windows, and `so` everywhere else. For static libraries, it is `a` everywhere. By convention MSVC static libraries use the `lib` suffix, but we use `a` to avoid a potential name clash with shared libraries which also generate import libraries with a `lib` suffix.

Set this to `[]`, or omit the keyword argument for the default behaviour.

native bool, default: false

Controls whether the target is compiled for the build or host machines.

objects array[extracted_obj | file | str]

List of object files that should be linked in this target.

Since 1.1.0 this can include generated files in addition to object files that you don't have source to or that object files produced by other build targets. In earlier release, generated object files had to be placed in `sources`.

override_options array[str] | dict[str | bool | int | array[str]], since 0.40.0

takes an array of strings in the same format as `project`'s `default_options` overriding the values of these options for this target only. (since 1.2.0): A dictionary may now be passed.

pic bool, since 0.36.0

Builds the library as positional independent code (so it can be linked into a shared library). This option has no effect on Windows and OS X since it doesn't make sense on Windows and PIC cannot be disabled on OS X.

pie bool, since 0.49.0

Build a positio-independent executable.

prelink bool, since 0.57.0

If `true` the object files in the target will be prelinked, meaning that it will contain only one prelinked object file rather than the individual object files.

rust_abi str, since 1.3.0

Set the specific ABI to compile (when compiling rust).- 'rust' (default): Create a "rlib" or "dylib" crate depending on the library type being build.
- 'c': Create a "cdylib" or "staticlib" crate depending on the library type being build.

rust_crate_type str, deprecated since 1.3.0, since 0.42.0

Set the specific type of rust crate to compile (when compiling rust).

If the target is an executable this defaults to "bin", the only allowed value.

If it is a static_library it defaults to "lib", and may be "lib", "staticlib", or "rlib". If "lib" then Rustc will pick a default, "staticlib" means a C ABI library, "rlib" means a Rust ABI.

If it is a shared_library it defaults to "lib", and may be "lib", "dylib", "cdylib", or "pro-macro". If "lib" then Rustc will pick a default, "cdylib" means a C ABI library, "dylib" means a Rust ABI, and "pro-macro" is a special rust procedural macro crate.

"pro-macro" is new in 0.62.0.

Since 1.3.0 this is deprecated and replaced by "rust_abi" keyword argument. `proc_macro` crates are now handled by the `rust.proc_macro()`[8] method.

rust_dependency_map dict[str], since 1.2.0

On rust targets this allows giving custom names to the crates that are linked into the target. For example, passing a dependency map of `{ 'gtk4': 'gtk' }` has the same effect of writing `gtk.package = "gtk4"` in the `dependencies` section of a Cargo.toml file, or `extern crate gtk4 as gtk` inside Rust code.

Since 1.10.0, the keys can be either crate names or target names.

shortname str, since 1.10.0

A string specifying a DLL name fitting to 8.3 limit on OS/2 of this shared library.

sources str | file | custom_tgt | custom_idx | generated_list | structured_src

Additional source files. Same as the source varargs.

soversion str | int

A string or integer specifying the soversion of this shared library, such as `0`. On Linux and Windows this is used to set the soversion (or equivalent) in the filename. For example, if `soversion` is `4`, a Windows DLL will be called `fo-4.dll` and one of the aliases of the Linux shared library would be `libfoo.so.4`. If this is not specified, the first part of `version` is used instead (see below). For example, if `version` is `3.6.0` and `soversion` is not defined, it is set to `3`.

target_type str

The actual target type to build

vala_args array[str | file]

Compiler flags for Vala. Unlike other languages this may contain Files

vala_gir str

If set, generates a GIR file with the given name. If this is unset then no GIR file will be generated.

vala_header str

On Vala targets, this provides a way to override the name of the generated C compatible header for targets that generate them.

If it is not set the default will be calculated from the target's name.

vala_shared_args array[str | file], since 1.3.0

Arguments that are only passed to a shared library Like `vala_args`, files is allowed in addition to string

vala_static_args array[str | file], since 1.3.0

Arguments that are only passed to a static library Like `vala_args`, files is allowed in addition to string

vala_vapi str

On Vala targets, this provides a way to override the name of the generated VAPI file.

If it is not set the default will be calculated from the target's name.

version str

A string specifying the version of this shared library, such as `1.1.0`. On Linux and OS X, this is used to set the shared library version in the filename, such as `libfoo.so.1.1.0` and `libfoo.1.1.0.dylib`. If this is not specified, `soversion` is used instead (see above).

vs_module_defs str | file | custom_tgt | custom_idx, since 1.3.0

Specify a Microsoft module definition file for controlling symbol exports, etc., on platforms where that is possible (e.g. Windows).

This can be used to expose which functions a shared_module loaded by an executable will be allowed to use.

win_subsystem str, default: 'console', since 0.56.0

Specifies the subsystem type to use on the Windows platform. Typical values include `console` for text mode programs and `windows` for gui apps. The value can also contain version specification such as `windows,6.0`. See MSDN documentation[9] for the full list.

 

configuration_data()

SYNOPSIS

cfg_data configuration_data([data])

DESCRIPTION

Creates an empty configuration object. You should add your configuration with the cfg_data method calls and finally use it in a call to configure_file.

OPTARGS

data dict[str | bool | int], since 0.49.0

Optional dictionary to specify an initial data set. If provided, each key/value pair is added into the cfg_data object as if the cfg_data.set method was called for each of them.

 

configure_file()

SYNOPSIS

file configure_file(

build_subdir:,
capture: false,
command:,
configuration:,
copy: false,
depfile:,
encoding: 'ut-8',
format: 'meson',
input:,
install: false,
install_dir:,
install_mode:,
install_tag:,
macro_name:,
output:,
output_format:,

)

DESCRIPTION

This function can run in three modes depending on the keyword arguments passed to it.

When a cfg_data object is passed to the `configuration:` keyword argument, it takes a template file as the `input:` (optional) and produces the `output:` (required) by substituting values from the configuration data as detailed in the configuration file documentation[11]. (since 0.49.0) A dictionary can be passed instead of a cfg_data object.

When an array of strings is passed to the `command:` keyword argument, it takes any source or configured file as the `input:` and assumes that the `output:` is produced when the specified command is run.

You can install the outputted file with the `install_dir:` kwarg, see below.

(since 0.47.0) When the `copy:` keyword argument is set to `true`, this function will copy the file provided in `input:` to a file in the build directory with the name `output:` in the current directory.

KWARGS

build_subdir str, since 1.10.0

Places the build results in a subdirectory of the given name rather than directly into the build directory. This does not affect the install directory, which uses install_dir. This allows inserting a directory name into the build path, either when needed to use the build result while building other targets or as a way to support multiple targets with the same basename by using unique build_subdir values for each one. To prevent collisions within the build directory, build_subdir is not allowed to match a file or directory in the source directory, nor contain '..' to refer to the parent of the build directory.

capture bool, default: false, since 0.41.0

When this argument is set to true, Meson captures `stdout` of the `command` and writes it to the target file specified as `output`.

command array[str | file]

As explained above, if specified, Meson does not create the file itself but rather runs the specified command, which allows you to do fully custom file generation. (since 0.52.0) The command can contain file objects and more than one file can be passed to the `input` keyword argument, see custom_target for details about string substitutions.

configuration cfg_data | dict[str | int | bool]

As explained above, when passed this will provide the replacement data for the input file (if provided) or key value pairs to be written to the output.

copy bool, default: false, since 0.47.0

As explained above, if specified Meson only copies the file from input to output.

depfile str, since 0.52.0

A dependency file that the command can write listing all the additional files this target depends on. A change in any one of these files triggers a reconfiguration.

encoding str, default: 'ut-8', since 0.47.0

Set the file encoding for the input and output file. The supported encodings are those of python3, see standar-encodings[12].

format str, default: 'meson', since 0.46.0

The format of defines. It defaults to `'meson'`, and so substitutes `#mesondefine` statements and variables surrounded by `@` characters, you can also use `'cmake'` to replace `#cmakedefine` statements and variables with the `${variable}` syntax. Finally you can use `'cmake@'` in which case substitutions will apply on `#cmakedefine` statements and variables with the `@variable@` syntax.

input str | file

The input file name. If it's not specified in configuration mode, all the variables in the `configuration:` object (see above) are written to the `output:` file.

install bool, default: false, since 0.50.0

When true, this generated file is installed during the install step, and `install_dir` must be set and not empty. When false, this generated file is not installed regardless of the value of `install_dir`. When omitted it defaults to true when `install_dir` is set and not empty, false otherwise.

install_dir str

The subdirectory to install the generated file to (e.g. `share/myproject`), if omitted or given the value of empty string, the file is not installed.

install_mode array[str | int], since 0.47.0

Specify the file mode in symbolic format and optionally the owner/uid and group/gid for the installed files.

See the `install_mode` kwarg of install_data for more information.

install_tag str, since 0.60.0

A string used by the `meson install-tags` command to install only a subset of the files. By default the file has no install tag which means it is not being installed when -tags` argument is specified.

macro_name str, since 1.3.0

When specified, macro guards will be used instead of '#pragma once'. The macro guard name will be the specified name.

output str

The output file name. (since 0.41.0) may contain `@PLAINNAME@` or `@BASENAME@` substitutions, as well as (since 1.5.0) their indexed versions, like `@PLAINNAME0@` or `@BASENAME0@`. In configuration mode, the permissions of the input file (if it is specified) are copied to the output file.

output_format str, since 0.47.0

The format of the output to generate when no input was specified. It defaults to `c`, in which case preprocessor directives will be prefixed with `#`, you can also use `nasm`, in which case the prefix will be `%`. (since 1.3.0) `json` format can also be used.

WARNINGS

the `install_mode` kwarg ignored integer values between 0.62- 1.1.0.

 

custom_target()

SYNOPSIS

custom_tgt custom_target(

[name],
build_always:,
build_always_stale: false,
build_by_default:,
build_subdir:,
capture: false,
command:,
console:,
depend_files:,
depends:,
depfile:,
env:,
feed: false,
input:,
install:,
install_dir:,
install_mode:,
install_tag:,
output:,

)

DESCRIPTION

Create a custom top level build target. The only positional argument is the name of this target and cannot contain path separators (`/` or ``). The name of custom target might not be used by every backends, for instance with the Ninja backend, `subdir/meson.build` containing the example below, `ninja-C builddir foo` or `ninja-C builddir subdir/foo` won't work, it is instead `ninja-C builddir subdir/file.txt`. However, `meson compile subdir/foo` is accepted.

custom_target('foo', output: 'file.txt', ...)

The files passed to `output:` cannot contain path separators. See the manual on custom build targets[13] for an explanation on where output files should be placed.

You can install the outputted files with the `install_dir:` kwarg, see below.

Since 0.60.0 the name argument is optional and defaults to the basename of the first output (`file.txt` in the example above).

The array of strings passed to the `command` keyword argument accept the following special string substitutions:

- `@INPUT@`: the full path to the input passed to `input`. If more than one input is specified, all of them will be substituted as separate arguments only if the command uses `'@INPUT@'` as a standalon-argument. For instance, this would not work: `command : ['cp', './@INPUT@']`, but this would: `command : ['cp', '@INPUT@']`.
- `@OUTPUT@`: the full path to the output passed to `output`. If more than one outputs are specified, the behavior is the same as `@INPUT@`.
- `@INPUT0@` `@INPUT1@` `...`: the full path to the input with the specified array index in `input`
- `@OUTPUT0@` `@OUTPUT1@` `...`: the full path to the output with the specified array index in `output`
- `@OUTDIR@`: the full path to the directory where the output(s) must be written
- `@DEPFILE@`: the full path to the dependency file passed to `depfile`
- `@PLAINNAME@`: the input filename, without a path
- `@PLAINNAME0@` `@PLAINNAME1@` `...` (since 1.5.0): the input filename without a path, with the specified array index in `input`
- `@BASENAME@`: the input filename, with extension removed
- `@BASENAME0@` `@BASENAME1@` `...` (since 1.5.0): the input filename with extension removed, with the specified array index in `input`
- `@PRIVATE_DIR@` (since 0.50.1): path to a directory where the custom target must store all its intermediate files.
- `@SOURCE_ROOT@`: the path to the root of the source tree. Depending on the backend, this may be an absolute or a relative to current workdir path.
- `@BUILD_ROOT@`: the path to the root of the build tree. Depending on the backend, this may be an absolute or a relative to current workdir path.
- `@CURRENT_SOURCE_DIR@`: this is the directory where the currently processed meson.build is located in. Depending on the backend, this may be an absolute or a relative to current workdir path.

(since 0.47.0) The `depfile` keyword argument also accepts the `@BASENAME@` and `@PLAINNAME@` substitutions.

The returned object also has methods that are documented in custom_tgt.

OPTARGS

name str

The unique id of the custom target

This posarg is optional since 0.60.0. It defaults to the basename of the first output.

KWARGS

build_always bool, deprecated since 0.47.0

If `true` this target is always considered out of date and is rebuilt every time. Equivalent to setting both `build_always_stale` and `build_by_default` to true.

build_always_stale bool, default: false, since 0.47.0

If `true` the target is always considered out of date. Useful for things such as build timestamps or revision control tags. The associated command is run even if the outputs are up to date.

build_by_default bool, since 0.38.0

Causes, when set to true, to have this target be built by default. This means it will be built when `meson compile` is called without any arguments. The default value is `false`.

(since 0.50.0) If `build_by_default` is explicitly set to false, `install` will no longer override it. If `build_by_default` is not set, `install` will still determine its default.

build_subdir str, since 1.10.0

Places the build results in a subdirectory of the given name rather than directly into the build directory. This does not affect the install directory, which uses install_dir. This allows inserting a directory name into the build path, either when needed to use the build result while building other targets or as a way to support multiple targets with the same basename by using unique build_subdir values for each one. To prevent collisions within the build directory, build_subdir is not allowed to match a file or directory in the source directory, nor contain '..' to refer to the parent of the build directory.

capture bool, default: false

There are some compilers that can't be told to write their output to a file but instead write it to standard output. When this argument is set to true, Meson captures `stdout` and writes it to the target file. Note that your command argument array may not contain `@OUTPUT@` when capture mode is active.

command array[str | file | exe | external_program]

Command to run to create outputs from inputs. The command may be strings or the return value of functions that return fil-like objects such as find_program, executable, configure_file, files, custom_target, etc. Meson will automatically insert the appropriate dependencies on targets and files listed in this keyword argument. Note: always specify commands in array form `['commandname', '-arg1', -arg2']` rather than as a string `'commandname-arg1-arg2'` as the latter will not work.

console bool, since 0.48.0

Keyword argument conflicts with `capture`, and is meant for commands that are resourc-intensive and take a long time to finish. With the Ninja backend, setting this will add this target to Ninja's `console` pool[14], which has special properties such as not buffering stdout and serializing all targets in this pool.

depend_files array[str | file]

files (str, file, or the return value of configure_file that this target depends on but are not listed in the `command` keyword argument. Useful for adding regen dependencies.

depends array[build_tgt | custom_tgt | custom_idx]

Specifies that this target depends on the specified target(s), even though it does not take any of them as a command line argument. This is meant for cases where you have a tool that e.g. does globbing internally. Usually you should just put the generated sources as inputs and Meson will set up all dependencies automatically (custom_idx was unavailable as a type between 0.60 and 1.4.0).

depfile str

A dependency file that the command can write listing all the additional files this target depends on, for example a C compiler would list all the header files it included, and a change in any one of these files triggers a recompilation.

(since 0.47.0) the `@BASENAME@` and `@PLAINNAME@` substitutions are also accepted.

env env | array[str] | dict[str], since 0.57.0

environment variables to set, such as `{'NAME1': 'value1', 'NAME2': 'value2'}` or `['NAME1=value1', 'NAME2=value2']`, or an env object which allows more sophisticated environment juggling.

feed bool, default: false, since 0.59.0

There are some compilers that can't be told to read their input from a file and instead read it from standard input. When this argument is set to `true`, Meson feeds the input file to `stdin`. Note that your argument array may not contain `@INPUT@` when feed mode is active.

input array[str | file]

Array of source files. (since 0.41.0) the array is flattened.

install bool

When true, one or more files of this target are installed during the install step (see `install_dir` for details).

install_dir str | array[str | bool]

If only one install_dir is provided, all outputs are installed there. Since 0.40.0 Allows you to specify the installation directory for each corresponding output. For example:

custom_target('differen-instal-dirs',

  output : ['first.file', 'second.file'],

  install : true,

  install_dir : ['somedir', 'otherdir'])

This would install `first.file` to `somedir` and `second.file` to `otherdir`.

To only install some outputs, pass `false` for the outputs that you don't want installed. For example:

    custom_target('onl-instal-second',

      output : ['first.file', 'second.file'],

      install : true,

      install_dir : [false, 'otherdir'])

This would install `second.file` to `otherdir` and not install `first.file`.

install_mode array[str | int], since 0.47.0

The file mode and optionally the owner/uid and group/gid. See the `install_mode` kwarg of install_data for more information.

install_tag array[str], since 0.60.0

An array of strings, one per output, used by the `meson install-tags` command to install only a subset of the files.

By default all outputs have no install tag which means they are not being installed when -tags` argument is specified. If only one tag is specified, it is assumed that all outputs have the same tag. `false` can be used for outputs that have no tag or are not installed.

output array[str]

Array of output files. These cannot contain path separators.

NOTES

Assuming that `command:` is executed by a POSIX `sh` shell is not portable, notably to Windows. Instead, consider using a `native: true` executable, or a python script.

WARNINGS

the `install_mode` kwarg ignored integer values between 0.60.0- 1.1.0.

 

debug()

SYNOPSIS

void debug(message, msg...)

since 0.63.0

DESCRIPTION

Write the argument string to the meson build log.

POSARGS

message str | int | bool | array[str | int | bool] | dict[str | int | bool], required

The message to print

VARARGS

msg str | int | bool | array[str | int | bool] | dict[str | int | bool], 0...N times

Additional parameters will be separated by spaces

 

declare_dependency()

SYNOPSIS

dep declare_dependency(

compile_args:,
d_import_dirs:,
d_module_versions:,
dependencies:,
extra_files:,
include_directories:,
link_args:,
link_whole:,
link_with:,
objects:,
sources:,
variables:,
version:,

)

DESCRIPTION

This function returns a dep object that behaves like the return value of dependency but is internal to the current build. One use case for this is in subprojects. This allows a subproject to easily specify how it should be used. This makes it interchangeable with the same dependency that is provided externally by the system. Another common use case is to declare project targets as dependencies so they may be used as dependencies of other build targets.

KWARGS

compile_args array[str]

Compile arguments to use.

d_import_dirs array[inc | str], since 0.62.0

the directories to add to the string search path (i.e. -J` switch for DMD). Must be inc objects or plain strings.

d_module_versions str | int | array[str | int], since 0.62.0

The D version identifiers[5] to add during the compilation of D source files.

dependencies array[dep]

Other dependencies needed to use this dependency.

extra_files array[str | file], since 1.2.0

extra files to add to targets. mostly used for IDE integration.

include_directories array[inc | str]

the directories to add to header search path, must be inc objects or (since 0.50.0) plain strings.

link_args array[str]

Link arguments to use.

link_whole array[lib], since 0.46.0

Libraries to link fully, same as executable.

link_with array[lib]

Libraries to link against.

objects array[extracted_obj], since 1.1.0

an array of object files, to be linked directly into the targets that use the dependency.

sources array[str | file | custom_tgt | custom_idx | generated_list]

sources to add to targets (or generated header files that should be built before sources including them are built)

variables dict[str] | array[str], since 0.54.0

a dictionary of arbitrary strings, this is meant to be used in subprojects where special variables would be provided via cmake or pk-config. since 0.56.0 it can also be an array of `'key=value'` strings.

version str

the version of this dependency, such as `1.2.3`. Defaults to the project version.

 

dependency()

SYNOPSIS

dep dependency(

names...,
allow_fallback:,
default_options:,
disabler: false,
fallback:,
include_type: 'preserve',
language:,
method: 'auto',
native: false,
not_found_message:,
required: true,
static:,
version:,

)

DESCRIPTION

Finds an external dependency (usually a library installed on your system) with the given name with `pk-config` and with CMake[15] if `pk-config` fails. Additionally, frameworks (OSX only) and librar-specific fallback detection logic[16] are also supported.

Since 0.60.0 more than one name can be provided, they will be tried in order and the first name to be found will be used. The fallback subproject will be used only if none of the names are found on the system. Once one of the name has been found, all other names are added into the cache so subsequent calls for any of those name will return the same value. This is useful in case a dependency could have different names, such as `png` and `libpng`.

Since 0.64.0* a dependency fallback can be provided by WrapDB. Simply download the database locally using `meson wrap updat-db` command and Meson will automatically fallback to subprojects provided by WrapDB if the dependency is not found on the system and the project does not ship their own `.wrap` file.

Dependencies can also be resolved in two other ways:

* if the same name was used in a `meson.override_dependency` prior to the call to `dependency`, the overriding dependency will be returned unconditionally; that is, the overriding dependency will be used independent of whether an external dependency is installed in the system. Typically, `meson.override_dependency` will have been used by a subproject.

* by a fallback subproject which, if needed, will be brought into the current build specification as if `subproject()` had been called. The subproject can be specified with the `fallback` argument. Alternatively, if the `fallback` argument is absent, since 0.55.0 Meson can automatically identify a subproject as a fallback if a wrap file provides[17] the dependency, or if a subproject has the same name as the dependency. In the latter case, the subproject must use `meson.override_dependency` to specify the replacement, or Meson will report a hard error. See the Wrap documentation[16] for more details. This automatic search can be controlled using the `allow_fallback` keyword argument.

If `dependency_name` is `''`, the dependency is always not found. So with `required: false`, this always returns a dependency object for which the `found()` method returns `false`, and which can be passed like any other dependency to the `dependencies:` keyword argument of a `build_target`. This can be used to implement a dependency which is sometimes not required e.g. in some branches of a conditional, or with a `fallback:` kwarg, can be used to declare an optional dependency that only looks in the specified subproject, and only if that's allowed by -wra-mode`.

The returned object dep also has additional methods.

VARARGS

names str, 1...N times, since 0.60.0

The names of the dependency to look up. The dependencies are looked up in the order they are provided here. The first found dependency will then be used. The fallback subproject will be used only if none of the names are found on the system. Once one of the name has been found, all other names are added into the cache so subsequent calls for any of those name will return the same value. This is useful in case a dependency could have different names, such as `png` and `libpng`.

NOTE: Before 0.60.0 only a single dependency name was allowed.

KWARGS

allow_fallback bool, since 0.56.0

Specifies whether Meson should automatically pick a fallback subproject in case the dependency is not found in the system. If `true` and the dependency is not found on the system, Meson will fallback to a subproject that provides this dependency. If `false`, Meson will not fallback even if a subproject provides this dependency. By default, Meson will do so if `required` is `true` or `enabled`[0]; see the Wrap documentation[16] for more details.

default_options array[str] | dict[str | bool | int | array[str]], since 0.38.0

An array of default option values that override those set in the subproject's `meson.options` (like `default_options` in project, they only have effect when Meson is run for the first time, and command line arguments override any default options in build files) (since 1.2.0): A dictionary may now be passed.

disabler bool, default: false, since 0.49.0

Returns a disabler object instead of a no-found dependency if this kwarg is set to `true` and the dependency couldn't be found.

fallback array[str] | str

Manually specifies a subproject fallback to use in case the dependency is not found in the system. This is useful if the automatic search is not applicable or if you want to support versions of Meson older than 0.55.0. If the value is an array `['subproj_name', 'subproj_dep']`, the first value is the name of the subproject and the second is the variable name in that subproject that contains a dependency object such as the return value of declare_dependency or dependency, etc. Note that this means the fallback dependency may be a no-found dependency, in which case the value of the `required:` kwarg will be obeyed. Since 0.54.0 the value can be a single string, the subproject name; in this case the subproject must use `meson.override_dependency('dependency_name', subproj_dep)` to specify the dependency object used in the superproject. If the value is an empty array it has the same effect as `allow_fallback: false`.

include_type str, default: 'preserve', since 0.52.0

An enum flag, marking how the dependency flags should be converted. Supported values are `'preserve'`, `'system'` and `'no-system'`. System dependencies may be handled differently on some platforms, for instance, using -isystem` instead of -I`, where possible. If `include_type` is set to `'preserve'`, no additional conversion will be performed.

language str, since 0.42.0

Defines what languag-specific dependency to find if it's available for multiple languages.

method str, default: 'auto', since 0.40.0

Defines the way the dependency is detected, the default is `auto` but can be overridden to be e.g. `qmake` for Qt development, and different dependencies support different values[18] for this (though `auto` will work on all of them)

native bool, default: false

If set to `true`, causes Meson to find the dependency on the build machine system rather than the host system (i.e. where the cross compiled binary will run on), usually only needed if you build a tool to be used during compilation.

not_found_message str, since 0.50.0

An optional string that will be printed as a message if the dependency was not found.

required bool | feature, default: true

When set to `false`, Meson will proceed with the build even if the dependency is not found.

When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

(since 0.47.0) The value of a `feature` option can also be passed.

static bool

Tells the dependency provider to try to get static libraries instead of dynamic ones (note that this is not supported by all dependency backends)

Leaving this value unset will result in an implementation defined default value. For most dependencies this means the value of the `prefer_static` option, but some custom dependencies have their own method for determining the most useful default option.

Since 0.60.0 it also sets `default_library` option accordingly on the fallback subproject if it was not set explicitly in `default_options` keyword argument.

Since 0.63.0 when the `prefer_static` option is used to calculate the default value.

version array[str] | str, since 0.37.0

Specifies the required version, a string containing a comparison operator followed by the version string, examples include `>1.0.0`, `<=2.3.5` or `3.1.4` for exact matching. You can also specify multiple restrictions by passing an array to this keyword argument, such as: `['>=3.14.0', '<=4.1.0']`. These requirements are never met if the version is unknown.

NOTES

This function supports additional librar-specific[15] keyword arguments that may also be accepted (e.g. `modules` specifies submodules to use for dependencies such as Qt5 or Boost. `components` allows the user to manually add CMake `COMPONENTS` for the `find_package` lookup)

 

disabler()

SYNOPSIS

disabler disabler()

since 0.44.0

DESCRIPTION

Returns a disabler object.

 

environment()

SYNOPSIS

env environment([env], method:, separator:)

since 0.35.0

DESCRIPTION

Returns an empty env object.

OPTARGS

env str | array[str] | dict[str] | dict[array[str]], since 0.52.0

If provided, each key/value pair is added into the env object as if env.set method was called for each of them. Since 0.62.0 arrays of strings are allowed in dictionary values. In that case values are joined using the separator.

KWARGS

method str, since 0.62.0

Must be one of 'set', 'prepend', or 'append' (defaults to 'set'). Controls if initial values defined in the first positional argument are prepended, appended or replace the current value of the environment variable.

separator str, since 0.62.0

The separator to use for the initial values defined in the first positional argument. If not explicitly specified, the default path separator for the host operating system will be used, i.e. ';' for Windows and ':' for UNIX/POSIX systems.

 

error()

SYNOPSIS

void error(message, msg...)

DESCRIPTION

Print the argument string and halts the build process.

POSARGS

message str, required

The message to print

VARARGS

msg str, 0...N times, since 0.58.0

Additional parameters will be separated by spaces

 

executable()

SYNOPSIS

exe executable(

target_name,
source...,
<lang>_args:,
<lang>_pch:,
android_exe_type: 'executable',
build_by_default: true,
build_rpath:,
build_subdir:,
d_debug:,
d_import_dirs:,
d_module_versions:,
d_unittest: false,
dependencies:,
export_dynamic:,
extra_files:,
gnu_symbol_visibility:,
gui_app: false,
implib:,
implicit_include_directories: true,
include_directories:,
install: false,
install_dir:,
install_mode:,
install_rpath:,
install_tag:,
link_args:,
link_depends:,
link_language:,
link_whole:,
link_with:,
name_prefix:,
name_suffix:,
native: false,
objects:,
override_options:,
pie:,
rust_crate_type:,
rust_dependency_map:,
sources:,
vala_args:,
vala_gir:,
vala_header:,
vala_vapi:,
vs_module_defs:,
win_subsystem: 'console',

)

DESCRIPTION

Creates a new executable. The first argument specifies its name and the remaining positional arguments define the input files to use.

The arrays for the kwargs (such as `sources`, `objects`, and `dependencies`) are always flattened, which means you can freely nest and add arrays while creating the final array.

The returned object also has methods that are documented in exe.

Since 1.3.0 executable names can be the same across multiple targets as long as they each have a different `name_suffix`.

POSARGS

target_name str, required

The unique name of the build target

VARARGS

source str | file | custom_tgt | custom_idx | generated_list, 0...N times

Input source to compile. The following types are supported:

- Strings relative to the current source directory
- file objects defined in any preceding build file
- The return value of configur-time generators such as configure_file
- The return value of buil-time generators such as custom_target or generator.process

These input files can be sources, objects, libraries, or any other file. Meson will automatically categorize them based on the extension and use them accordingly. For instance, sources (`.c`, `.cpp`, `.vala`, `.rs`, etc) will be compiled and objects (`.o`, `.obj`) and libraries (`.so`, `.dll`, etc) will be linked.

With the Ninja backend, Meson will create a buil-time orde-only dependency[3] on all generated input files, including unknown files. This is needed to bootstrap the generation of the real dependencies in the depfile[4] generated by your compiler to determine when to rebuild sources. Ninja relies on this dependency file for all input files, generated and no-generated. The behavior is similar for other backends.

KWARGS

<lang>_args array[str]

compiler flags to use for the given language; eg: `cpp_args` for C++

<lang>_pch str

precompiled header file to use for the given language

android_exe_type str, default: 'executable', since 1.8.0

Specifies the intended target of the executable. This can either be `executable`, if the intended usecase is to run the executable using fork + exec, or `application` if the executable is supposed to be loaded as shared object by the android runtime.

build_by_default bool, default: true, since 0.38.0

Causes, when set to `true`, to have this target be built by default. This means it will be built when `meson compile` is called without any arguments. The default value is `true` for all built target types.

build_rpath str, since 0.42.0

A string to add to target's rpath definition in the build dir, but which will be removed on install

build_subdir str, since 1.10.0

Places the build results in a subdirectory of the given name rather than directly into the build directory. This does not affect the install directory, which uses install_dir. This allows inserting a directory name into the build path, either when needed to use the build result while building other targets or as a way to support multiple targets with the same basename by using unique build_subdir values for each one. To prevent collisions within the build directory, build_subdir is not allowed to match a file or directory in the source directory, nor contain '..' to refer to the parent of the build directory.

d_debug array[str]

The D version identifiers[5] to add during the compilation of D source files.

d_import_dirs array[inc | str], since 0.62.0

the directories to add to the string search path (i.e. -J` switch for DMD). Must be inc objects or plain strings.

d_module_versions array[str | int]

List of module version identifiers set when compiling D sources.

d_unittest bool, default: false

When set to true, the D modules are compiled in debug mode.

dependencies array[dep]

one or more dependency objects created with dependency or compiler.find_library (for external deps) or declare_dependency (for deps built by the project)

export_dynamic bool, since 0.45.0

when set to true causes the target's symbols to be dynamically exported, allowing modules built using the shared_module function to refer to functions, variables and other symbols defined in the executable itself.

extra_files str | file

Not used for the build itself but are shown as source files in IDEs that group files by targets (such as Visual Studio).

These may only be static sources.

gnu_symbol_visibility str, since 0.48.0

Specifies how symbols should be exported, see e.g the GCC Wiki[6] for more information. This value can either be an empty string or one of `default`, `internal`, `hidden`, `protected` or `inlineshidden`, which is the same as `hidden` but also includes things like C++ implicit constructors as specified in the GCC manual. Ignored on compilers that do not support GNU visibility arguments. See also `snippets.symbol_visibility_header()`[7] method to help with defining public API.

gui_app bool, default: false, deprecated since 0.56.0

When set to true flags this target as a GUI application on platforms where this makes a difference, deprecated since 0.56.0, use `win_subsystem` instead.

implib bool | str, since 0.42.0

When set to a string, that will be the name of a generated import library.

Since 1.10.0 passing a boolean value is deprecated.

When set to true, an import library is generated for the executable (the name of the import library is based on exe_name). Alternatively, when set to a string, that gives the base name for the import library. The import library is used when the returned build target object appears in `link_with:` elsewhere. Only has any effect on platforms where that is meaningful (e.g. Windows). Implies the `export_dynamic` argument.

implicit_include_directories bool, default: true, since 0.42.0

Controls whether Meson adds the current source and build directories to the include path

include_directories array[inc | str]

one or more objects created with the include_directories function, or (since 0.50.0) strings, which will be transparently expanded to include directory objects

install bool, default: false

When set to true, this executable should be installed.

install_dir str

override install directory for this file. If the value is a relative path, it will be considered relative the `prefix` option. For example, if you want to install plugins into a subdir, you'd use something like this: `install_dir : get_option('libdir') / 'projectnam-1.0'`.

install_mode array[str | int], since 0.47.0

Specify the file mode in symbolic format and optionally the owner/uid and group/gid for the installed files.

See the `install_mode` kwarg of install_data for more information.

install_rpath str

A string to set the target's rpath to after install (but not before that). On Windows, this argument has no effect.

install_tag str, since 0.60.0

A string used by the `meson install-tags` command to install only a subset of the files. By default all build targets have the tag `runtime` except for static libraries that have the `devel` tag.

link_args array[str]

Flags to use during linking. You can use UNI-style flags here for all platforms.

link_depends str | file | custom_tgt | custom_idx

Strings, files, or custom targets the link step depends on such as a symbol visibility map. The purpose is to automatically trigger a r-link (but not a r-compile) of the target when this file changes.

link_language str, since 0.51.0

Makes the linker for this target be for the specified language. It is generally unnecessary to set this, as Meson will detect the right linker to use in most cases. There are only two cases where this is needed. One, your main function in an executable is not in the language Meson picked, or second you want to force a library to use only one ABI.

(broken until 0.55.0)

link_whole array[lib | custom_tgt | custom_idx], since 0.40.0

Links all contents of the given static libraries whether they are used or not, equivalent to the -Wl-whol-archive` argument flag of GCC, or the '/WHOLEARCHIVE' MSVC linker option. This allows the linked target to r-export symbols from all objects in the static libraries.

(since 0.41.0) If passed an array that array will be flattened.

(since 0.51.0) This argument also accepts outputs produced by custom targets. The user must ensure that the output is a library in the correct format.

link_with array[lib | custom_tgt | custom_idx]

One or more shared or static libraries (built by this project) that this target should be linked with. (since 0.41.0) If passed an array that array will be flattened. (since 0.51.0) The arguments can also be custom targets. In this case Meson will assume that merely adding the output file in the linker command line is sufficient to make linking work. If this is not sufficient, then the build system writer must write all other steps manually.

name_prefix str | array[void]

The string that will be used as the prefix for the target output filename by overriding the default (only used for libraries). By default this is `lib` on all platforms and compilers, except for MSVC shared libraries where it is omitted to follow convention, and Cygwin shared libraries where it is `cyg`.

Set this to `[]`, or omit the keyword argument for the default behaviour.

name_suffix str | array[void]

The string that will be used as the extension for the target by overriding the default. By default on Windows this is `exe` for executables and on other platforms it is omitted.

For shared libraries, the default value is `dylib` on macOS, `dll` on Windows, and `so` everywhere else. For static libraries, it is `a` everywhere. By convention MSVC static libraries use the `lib` suffix, but we use `a` to avoid a potential name clash with shared libraries which also generate import libraries with a `lib` suffix.

Set this to `[]`, or omit the keyword argument for the default behaviour.

native bool, default: false

Controls whether the target is compiled for the build or host machines.

objects array[extracted_obj | file | str]

List of object files that should be linked in this target.

Since 1.1.0 this can include generated files in addition to object files that you don't have source to or that object files produced by other build targets. In earlier release, generated object files had to be placed in `sources`.

override_options array[str] | dict[str | bool | int | array[str]], since 0.40.0

takes an array of strings in the same format as `project`'s `default_options` overriding the values of these options for this target only. (since 1.2.0): A dictionary may now be passed.

pie bool, since 0.49.0

Build a positio-independent executable.

rust_crate_type str, deprecated since 1.3.0, since 0.42.0

Set the specific type of rust crate to compile (when compiling rust).

If the target is an executable this defaults to "bin", the only allowed value.

If it is a static_library it defaults to "lib", and may be "lib", "staticlib", or "rlib". If "lib" then Rustc will pick a default, "staticlib" means a C ABI library, "rlib" means a Rust ABI.

If it is a shared_library it defaults to "lib", and may be "lib", "dylib", "cdylib", or "pro-macro". If "lib" then Rustc will pick a default, "cdylib" means a C ABI library, "dylib" means a Rust ABI, and "pro-macro" is a special rust procedural macro crate.

"pro-macro" is new in 0.62.0.

Since 1.3.0 this is deprecated and replaced by "rust_abi" keyword argument. `proc_macro` crates are now handled by the `rust.proc_macro()`[8] method.

rust_dependency_map dict[str], since 1.2.0

On rust targets this allows giving custom names to the crates that are linked into the target. For example, passing a dependency map of `{ 'gtk4': 'gtk' }` has the same effect of writing `gtk.package = "gtk4"` in the `dependencies` section of a Cargo.toml file, or `extern crate gtk4 as gtk` inside Rust code.

Since 1.10.0, the keys can be either crate names or target names.

sources str | file | custom_tgt | custom_idx | generated_list | structured_src

Additional source files. Same as the source varargs.

vala_args array[str | file]

Compiler flags for Vala. Unlike other languages this may contain Files

vala_gir str

If set, generates a GIR file with the given name. If this is unset then no GIR file will be generated.

vala_header str

On Vala targets, this provides a way to override the name of the generated C compatible header for targets that generate them.

If it is not set the default will be calculated from the target's name.

vala_vapi str

On Vala targets, this provides a way to override the name of the generated VAPI file.

If it is not set the default will be calculated from the target's name.

vs_module_defs str | file | custom_tgt | custom_idx, since 1.3.0

Specify a Microsoft module definition file for controlling symbol exports, etc., on platforms where that is possible (e.g. Windows).

This can be used to expose which functions a shared_module loaded by an executable will be allowed to use.

win_subsystem str, default: 'console', since 0.56.0

Specifies the subsystem type to use on the Windows platform. Typical values include `console` for text mode programs and `windows` for gui apps. The value can also contain version specification such as `windows,6.0`. See MSDN documentation[9] for the full list.

WARNINGS

The `link_language` kwarg was broken until 0.55.0

 

files()

SYNOPSIS

array[file] files(file...)

DESCRIPTION

This command takes the strings given to it in arguments and returns corresponding File objects that you can use as sources for build targets. The difference is that file objects remember the subdirectory they were defined in and can be used anywhere in the source tree.

VARARGS

file str, 0...N times

Path to the file.

EXAMPLE

As an example suppose you have source file `foo.cpp` in subdirectory `bar1` and you would like to use it in a build target that is defined in `bar2`. To make this happen you first create the object in `bar1` like this:

    foofile = files('foo.cpp')

Then you can use it in `bar2` like this:

    executable('myprog', 'myprog.cpp', foofile, ...)

Meson will then do the right thing.

 

find_program()

SYNOPSIS

external_program find_program(

program_name,
fallback...,
default_options:,
dirs:,
disabler: false,
native: false,
required: true,
version:,
version_argument:,

)

DESCRIPTION

`program_name` here is a string that can be an executable or script to be searched for in `PATH` or other places inside the project. The search order is:

1. Program overrides set via meson.override_find_program 1. `[provide]` sections[16]
  in subproject wrap files, if `wrap_mode`[19] is
  set to `forcefallback` 1. `[binaries]` section[20] in your machine files 1. Directories provided using the `dirs:` kwarg (see below) 1. Project's source tree relative to the current subdir
   - If you use the return value of configure_file, the
     current subdir inside the build tree is used instead 1. `PATH` environment variable 1. `[provide]` sections[16] in
  subproject wrap files, if `wrap_mode`[18] is
  set to anything other than `nofallback`

Meson will also autodetect scripts with a shebang line and run them with the executable/interpreter specified in it both on Windows (because the command invocator will reject the command otherwise) and Unixes (if the script file does not have the executable bit set). Hence, you must not manually add the interpreter while using this script as part of an array of commands. Since 0.50.0 if the "python3" program is requested and it is not found in the system, Meson will return its current interpreter.

If you need to check for a program in a no-standard location, you can just pass an absolute path to `find_program`, e.g.

setcap = find_program('setcap', '/usr/sbin/setcap', '/sbin/setcap', required : false)

It is also possible to pass an array to `find_program` in case you need to construct the set of paths to search on the fly:

setcap = find_program(['setcap', '/usr/sbin/setcap', '/sbin/setcap'], required : false)

Since 1.2.0 `find_program('meson')` is automatically overridden to the Meson command used to execute the build script.

The returned external_program object also has documented methods.

POSARGS

program_name str | file, required

The name of the program to search, or a file object to be used without searching.

VARARGS

fallback str | file, 0...N times, since 0.37.0

These parameters are used as fallback names to search for. This is meant to be used for cases where the program may have many alternative names, such as `foo` and `foo.py`. The function will check for the arguments one by one and the first one that is found is returned.

KWARGS

default_options array[str] | dict[str | bool | int | array[str]], since 1.3.0

An array of default option values that override those set in the subproject's `meson.options` (like `default_options` in project, they only have effect when Meson is run for the first time, and command line arguments override any default options in build files)

dirs array[str], since 0.53.0

extra array of absolute paths where to look for program names.

disabler bool, default: false, since 0.49.0

If `true` and the program couldn't be found, return a disabler object instead of a no-found object.

native bool, default: false, since 0.43.0

Defines how this executable should be searched. By default it is set to `false`, which causes Meson to first look for the executable in the cross file (when cross building) and if it is not defined there, then from the system. If set to `true`, the cross file is ignored and the program is only searched from the system.

required bool | feature, default: true

When `true`, Meson will abort if no program can be found. If `required` is set to `false`, Meson continue even if none of the programs can be found. You can then use the `.found()` method on the returned external_program to check whether it was found or not. (since 0.47.0) The value of a `feature`[0] option can also be passed to the `required` keyword argument.

version str | array[str], since 0.52.0

Specifies the required version, see dependency for argument format. By default, the version of the program is determined by running `program_name-version` command. If stdout is empty it fallbacks to stderr. If the output contains more text than simply a version number, only the first occurrence of numbers separated by dots is kept. If the output is more complicated than that, the version checking will have to be done manually using run_command.

version_argument str, since 1.5.0

Specifies the argument to pass when trying to find the version of the program. If this is unspecified, `program_name-version` will be used.

 

generator()

SYNOPSIS

generator generator(

exe,
arguments:,
capture: false,
depends:,
depfile:,
output:,

)

DESCRIPTION

See also: custom_target

This function creates a generator object that can be used to run custom compilation commands. The only positional argument is the executable to use. It can either be a sel-built executable or one returned by find_program.

The template strings passed to all the keyword arguments accept the following special substitutions:

- `@PLAINNAME@`: the complete input file name, e.g: `foo.c` becomes `foo.c` (unchanged)
- `@BASENAME@`: the base of the input filename, e.g.: `foo.c.y` becomes `foo.c` (extension is removed)

Each string passed to the `output` keyword argument must be constructed using one or both of these two substitutions.

In addition to the above substitutions, the `arguments` keyword argument also accepts the following:

- `@OUTPUT@`: the full path to the output file
- `@INPUT@`: the full path to the input file
- `@DEPFILE@`: the full path to the depfile
- `@SOURCE_DIR@`: the full path to the root of the source tree
- `@CURRENT_SOURCE_DIR@`: this is the directory where the currently processed meson.build is located in
- `@BUILD_DIR@`: the full path to the root of the build dir where the output will be placed

NOTE: Generators should only be used for outputs that will only be used as inputs for a build_target or a custom_target. When you use the processed output of a generator in multiple targets, the generator will be run multiple times to create outputs for each target. Each output will be created in a targe-private directory `@BUILD_DIR@`.

If you want to generate files for general purposes such as for generating headers to be used by several sources, or data that will be installed, and so on, use a custom_target instead.

POSARGS

exe exe | external_program, required

Executable for the command to run

KWARGS

arguments array[str]

An array of template strings that will be the command line arguments passed to the executable.

capture bool, default: false, since 0.43.0

When this argument is set to true, Meson captures `stdout` of the `executable` and writes it to the target file specified as `output`.

depends array[build_tgt | custom_tgt | custom_idx], since 0.51.0

An array of build targets that must be built before this generator can be run. This is used if you have a generator that calls a second executable that is built in this project (custom_idx was not available between 0.60 and 1.4.0).

depfile str

A template string pointing to a dependency file that a generator can write listing all the additional files this target depends on, for example a C compiler would list all the header files it included, and a change in any one of these files triggers a recompilation,

output array[str]

Template string (or array of template strings) defining how an output file name is (or multiple output names are) generated from a single source file name.

 

get_option()

SYNOPSIS

str | int | bool | feature | array[str | int | bool] get_option(

option_name,

)

DESCRIPTION

Obtains the value of the project build option[21] specified in the positional argument.

Note that the value returned for buil-in options that end in `dir` such as `bindir` and `libdir` is usually a path relative to (and inside) the `prefix` but you should not rely on that, as it can also be an absolute path in some cases[22]. `install_dir` arguments[23] handle that as expected but if you need an absolute path, e.g. to use in a define etc., you should use the path concatenation operator like this: `get_option('prefix') / get_option('localstatedir')`. Never manually join paths as if they were strings.

For options of type `feature` a feature option object is returned instead of a string. See `feature` options[0] documentation for more details.

For options that are specified pe-machine[24] `get_option()` retrieves the value of the option for the build machine if the argument starts with `build.`.

POSARGS

option_name str, required

Name of the option to query

 

get_variable()

SYNOPSIS

any get_variable(variable_name, [default])

DESCRIPTION

This function can be used to dynamically obtain a variable. `res = get_variable(varname, fallback)` takes the value of `varname` (which must be a string) and stores the variable of that name into `res`. If the variable does not exist, the variable `fallback` is stored to `res`instead. If a fallback is not specified, then attempting to read a no-existing variable will cause a fatal error.

POSARGS

variable_name str, required

Name of the variable to get

OPTARGS

default any

Fallback value to return when the variable does not exist

 

import()

SYNOPSIS

module import(module_name, disabler:, required: true)

DESCRIPTION

Imports the given extension module. Returns an object that can be used to call the methods of the module. Here's an example for a hypothetical `testmod` module.

POSARGS

module_name str, required

Name of the module to import.

KWARGS

disabler bool, since 0.59.0

Returns a disabler object when not found.

required bool | feature, default: true, since 0.59.0

When set to `false`, Meson will proceed with the build even if the module is not found. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

EXAMPLE

tmod = import('testmod')
tmod.do_something()

 

include_directories()

SYNOPSIS

inc include_directories(includes..., is_system: false)

DESCRIPTION

Returns an opaque object which contains the directories (relative to the current directory) given in the positional arguments. The result can then be passed to the `include_directories:` keyword argument when building executables or libraries. You can use the returned object in any subdirectory you want, Meson will make the paths work automatically.

Note that this function call itself does not add the directories into the search path, since there is no global search path. For something like that, see `add_project_arguments()`.

See also `implicit_include_directories` parameter of executable, which adds current source and build directories to include path.

Each directory given is converted to two include paths: one that is relative to the source root and one relative to the build root.

VARARGS

includes str, 0...N times

Include paths to add.

KWARGS

is_system bool, default: false

If set to `true`, flags the specified directories as system directories. This means that they will be used with the -isystem` compiler argument rather than -I` on compilers that support this flag (in practice everything except Visual Studio).

EXAMPLE

For example, with the following source tree layout in `/home/user/project.git`:

`meson.build`:

project(...)

subdir('include')
subdir('src')

...

`include/meson.build`:

inc = include_directories('.')

...

`src/meson.build`:

sources = [...]

executable('som-tool', sources,

  include_directories : inc,

  ...)

...

If the build tree is `/tmp/buil-tree`, the following include paths will be added to the `executable()` call: -I/tmp/buil-tree/include-I/home/user/project.git/include`.

 

install_data()

SYNOPSIS

void install_data(

file...,
follow_symlinks: true,
install_dir:,
install_mode:,
install_tag:,
preserve_path: false,
rename:,
sources:,

)

DESCRIPTION

Installs files from the source tree that are listed as positional arguments. Please note that this can only install static files from the source tree. Generated files are installed via the `install_dir:` kwarg on the respective generators, such as `custom_target()` or `configure_file()`.

See Installing[22] for more examples.

VARARGS

file file | str, 0...N times

Files to install.

KWARGS

follow_symlinks bool, default: true, since 1.3.0

If true, dereferences links and copies their target instead. The default value will become false in the future.

install_dir str

The absolute or relative path to the installation directory. If this is a relative path, it is assumed to be relative to the prefix.

If omitted, the directory defaults to `{datadir}/{projectname}` (since 0.45.0).

install_mode array[str | int], since 0.38.0

specify the file mode in symbolic format and optionally the owner/uid and group/gid for the installed files. For example:

`install_mode: 'r---'` for just the file mode

`install_mode: ['r---', 'nobody', 'nogroup']` for the file mode and the user/group

`install_mode: ['r--', 0, 0]` for the file mode and uid/gid

To leave any of these three as the default, specify `false`.

install_tag str, since 0.60.0

A string used by the `meson install-tags` command to install only a subset of the files. By default these files have no install tag which means they are not being installed when -tags` argument is specified.

preserve_path bool, default: false, since 0.64.0

Disable stripping chil-directories from data files when installing.

This is equivalent to GNU Automake's `nobase` option.

rename array[str], since 0.46.0

If specified renames each source file into corresponding file from `rename` array. Nested paths are allowed and they are joined with `install_dir`. Length of `rename` array must be equal to the number of sources.

sources array[file | str]

Additional files to install.

WARNINGS

the `install_mode` kwarg ignored integer values between 0.59.0- 1.1.0. an omitted `install_dir` kwarg did not work correctly inside of a subproject until 1.3.0. an omitted `install_dir` kwarg did not work correctly when combined with the `preserve_path` kwarg until 1.3.0.

 

install_emptydir()

SYNOPSIS

void install_emptydir(dirpath..., install_mode:, install_tag:)

since 0.60.0

DESCRIPTION

Installs a new directory entry to the location specified by the positional argument. If the directory exists and is not empty, the contents are left in place.

VARARGS

dirpath str, 0...N times

Directory to create during installation.

KWARGS

install_mode array[str | int]

Specify the file mode in symbolic format and optionally the owner/uid and group/gid for the created directory.

See the `install_mode` kwarg of install_data for more information.

install_tag str

A string used by the `meson install-tags` command to install only a subset of the files. By default this directory has no install tag which means it is not installed when the -tags` argument is specified.

WARNINGS

the `install_mode` kwarg ignored integer values before 1.1.0.

 

install_headers()

SYNOPSIS

void install_headers(

file...,
follow_symlinks: true,
install_dir:,
install_mode:,
preserve_path: false,
subdir:,

)

DESCRIPTION

Installs the specified header files from the source tree into the system header directory (usually `/{prefix}/include`) during the install step. This directory can be overridden by specifying it with the `install_dir` keyword argument. If you just want to install into a subdirectory of the system header directory, then use the `subdir` argument. As an example if this has the value `myproj` then the headers would be installed to `/{prefix}/include/myproj`.

Please note that this can only install static files from the source tree. Generated files are installed via the `install_dir:` kwarg on the respective generators, such as `custom_target()` or `configure_file().

VARARGS

file file | str, 0...N times

Header files to install.

KWARGS

follow_symlinks bool, default: true, since 1.3.0

If true, dereferences links and copies their target instead. The default value will become false in the future.

install_dir str

Where to install to.

install_mode array[str | int], since 0.47.0

Specify the file mode in symbolic format and optionally the owner/uid and group/gid for the installed files.

See the `install_mode` kwarg of install_data for more information.

preserve_path bool, default: false, since 0.63.0

Disable stripping chil-directories from header files when installing.

This is equivalent to GNU Automake's `nobase` option.

subdir str

Install to the `subdir` subdirectory of the default includedir.

Incompatible with the `install_dir` kwarg.

WARNINGS

the `install_mode` kwarg ignored integer values between 0.59.0- 1.1.0.

EXAMPLE

For example, this will install `common.h` and `kola.h` into `/{prefix}/include`:

install_headers('common.h', 'proj/kola.h')

This will install `common.h` and `kola.h` into `/{prefix}/include/myproj`:

install_headers('common.h', 'proj/kola.h', subdir : 'myproj')

This will install `common.h` and `kola.h` into `/{prefix}/cust/myproj`:

install_headers('common.h', 'proj/kola.h', install_dir : 'cust', subdir : 'myproj')

This will install `common.h` into `/{prefix}/include` and `kola.h` into `/{prefix}/include/proj/`:

install_headers('common.h, 'proj/kola.h', preserve_path : true)

 

install_man()

SYNOPSIS

void install_man(file..., install_dir:, install_mode:, locale:)

DESCRIPTION

Installs the specified man files from the source tree into system's man directory during the install step. This directory can be overridden by specifying it with the `install_dir` keyword argument.

(since 0.49.0) [manpages are no longer compressed implicitly][install_man_49].

[install_man_49]: https://mesonbuild.com/Releas-note-fo--4-0.html#manpage-ar-n-longe-compresse-implicitly

VARARGS

file file | str, 0...N times

Man pages to install.

KWARGS

install_dir str

Where to install to.

install_mode array[str | int], since 0.47.0

Specify the file mode in symbolic format and optionally the owner/uid and group/gid for the installed files.

See the `install_mode` kwarg of install_data for more information.

locale str, since 0.58.0

Can be used to specify the locale into which the man page will be installed within the manual page directory tree. An example manual might be `foo.fr.1` with a locale of `fr`, such that `{mandir}/{locale}/man{num}/foo.1` becomes the installed file.

WARNINGS

the `install_mode` kwarg ignored integer values between 0.59.0- 1.1.0.

 

install_subdir()

SYNOPSIS

void install_subdir(

subdir_name,
exclude_directories:,
exclude_files:,
follow_symlinks: true,
install_dir:,
install_mode:,
install_tag:,
strip_directory: false,

)

DESCRIPTION

Installs the entire given subdirectory and its contents from the source tree to the location specified by the keyword argument `install_dir`.

(since 0.45.0, deprecated since 0.60.0) If the subdirectory does not exist in the source tree, an empty directory is created in the specified location. A newly created subdirectory may only be created in the keyword argument `install_dir`. There are a number of flaws with this method, and it was never intentionally designed to work this way, please use install_emptydir instead.

POSARGS

subdir_name str, required

The su-directory to install

KWARGS

exclude_directories array[str], since 0.47.0

An array of directory names that should not be installed. Names are interpreted as paths relative to the `subdir_name` location.

exclude_files array[str]

An array of file names that should not be installed. Names are interpreted as paths relative to the `subdir_name` location.

follow_symlinks bool, default: true, since 1.3.0

If true, dereferences links and copies their target instead. The default value will become false in the future.

install_dir str

Where to install to.

install_mode array[str | int], since 0.47.0

Specify the file mode in symbolic format and optionally the owner/uid and group/gid for the installed files.

See the `install_mode` kwarg of install_data for more information.

install_tag str, since 0.60.0

A string used by the `meson install-tags` command to install only a subset of the files. By default these files have no install tag which means they are not being installed when -tags` argument is specified.

strip_directory bool, default: false, since 0.45.0

Install directory contents. If `strip_directory=true` only the last component of the source path is used.

WARNINGS

the `install_mode` kwarg ignored integer values between 0.59.0- 1.1.0.

EXAMPLE

For a given directory `foo`:

text
foo/

  bar/

    file1

  file2

`install_subdir('foo', install_dir : 'share', strip_directory : false)` creates

text
share/

  foo/

    bar/

      file1

    file2

`install_subdir('foo', install_dir : 'share', strip_directory : true)` creates

text
share/

  bar/

    file1

  file2

`install_subdir('foo/bar', install_dir : 'share', strip_directory : false)` creates

text
share/

  bar/

    file1

`install_subdir('foo/bar', install_dir : 'share', strip_directory : true)` creates

text
share/

  file1

`install_subdir('new_directory', install_dir : 'share')` creates

text
share/

  new_directory/

 

install_symlink()

SYNOPSIS

void install_symlink(

link_name,
install_dir:,
install_tag:,
pointing_to:,

)

since 0.61.0

DESCRIPTION

Installs a symbolic link to `pointing_to` target under install_dir.

POSARGS

link_name str, required

Name of the created link under `install_dir`. It cannot contain path separators. Those should go in `install_dir`.

KWARGS

install_dir str, required

The absolute or relative path to the installation directory for the links. If this is a relative path, it is assumed to be relative to the prefix.

install_tag str

A string used by the `meson install-tags` command to install only a subset of the files. By default these files have no install tag which means they are not being installed when -tags` argument is specified.

pointing_to str, required

Target to point the link to. Can be absolute or relative and that will be respected when creating the link.

 

is_disabler()

SYNOPSIS

bool is_disabler(var)

since 0.52.0

DESCRIPTION

Returns true if a variable is a disabler and false otherwise.

POSARGS

var any, required

The variable to test

 

is_variable()

SYNOPSIS

bool is_variable(var)

since 0.52.0

DESCRIPTION

Returns true if a variable of the given name exists and false otherwise.

POSARGS

var str, required

The variable to test

 

jar()

SYNOPSIS

jar jar(

target_name,
source...,
<lang>_args:,
<lang>_pch:,
build_by_default: true,
build_rpath:,
build_subdir:,
d_debug:,
d_import_dirs:,
d_module_versions:,
d_unittest: false,
dependencies:,
extra_files:,
gnu_symbol_visibility:,
gui_app: false,
implicit_include_directories: true,
include_directories:,
install: false,
install_dir:,
install_mode:,
install_rpath:,
install_tag:,
java_resources:,
link_args:,
link_depends:,
link_language:,
link_whole:,
link_with:,
main_class:,
name_prefix:,
name_suffix:,
native: false,
objects:,
override_options:,
rust_crate_type:,
rust_dependency_map:,
sources:,
vala_args:,
vala_gir:,
vala_header:,
vala_vapi:,
win_subsystem: 'console',

)

DESCRIPTION

Build a jar from the specified Java source files. Keyword arguments are the same as executable's, with the addition of `main_class` which specifies the main class to execute when running the jar with `java-jar file.jar`.

POSARGS

target_name str, required

The unique name of the build target

VARARGS

source str | file | custom_tgt | custom_idx | generated_list, 0...N times

Input source to compile. The following types are supported:

- Strings relative to the current source directory
- file objects defined in any preceding build file
- The return value of configur-time generators such as configure_file
- The return value of buil-time generators such as custom_target or generator.process

These input files can be sources, objects, libraries, or any other file. Meson will automatically categorize them based on the extension and use them accordingly. For instance, sources (`.c`, `.cpp`, `.vala`, `.rs`, etc) will be compiled and objects (`.o`, `.obj`) and libraries (`.so`, `.dll`, etc) will be linked.

With the Ninja backend, Meson will create a buil-time orde-only dependency[3] on all generated input files, including unknown files. This is needed to bootstrap the generation of the real dependencies in the depfile[4] generated by your compiler to determine when to rebuild sources. Ninja relies on this dependency file for all input files, generated and no-generated. The behavior is similar for other backends.

KWARGS

<lang>_args array[str]

compiler flags to use for the given language; eg: `cpp_args` for C++

<lang>_pch str

precompiled header file to use for the given language

build_by_default bool, default: true, since 0.38.0

Causes, when set to `true`, to have this target be built by default. This means it will be built when `meson compile` is called without any arguments. The default value is `true` for all built target types.

build_rpath str, since 0.42.0

A string to add to target's rpath definition in the build dir, but which will be removed on install

build_subdir str, since 1.10.0

Places the build results in a subdirectory of the given name rather than directly into the build directory. This does not affect the install directory, which uses install_dir. This allows inserting a directory name into the build path, either when needed to use the build result while building other targets or as a way to support multiple targets with the same basename by using unique build_subdir values for each one. To prevent collisions within the build directory, build_subdir is not allowed to match a file or directory in the source directory, nor contain '..' to refer to the parent of the build directory.

d_debug array[str]

The D version identifiers[5] to add during the compilation of D source files.

d_import_dirs array[inc | str], since 0.62.0

the directories to add to the string search path (i.e. -J` switch for DMD). Must be inc objects or plain strings.

d_module_versions array[str | int]

List of module version identifiers set when compiling D sources.

d_unittest bool, default: false

When set to true, the D modules are compiled in debug mode.

dependencies array[dep]

one or more dependency objects created with dependency or compiler.find_library (for external deps) or declare_dependency (for deps built by the project)

extra_files str | file

Not used for the build itself but are shown as source files in IDEs that group files by targets (such as Visual Studio).

These may only be static sources.

gnu_symbol_visibility str, since 0.48.0

Specifies how symbols should be exported, see e.g the GCC Wiki[6] for more information. This value can either be an empty string or one of `default`, `internal`, `hidden`, `protected` or `inlineshidden`, which is the same as `hidden` but also includes things like C++ implicit constructors as specified in the GCC manual. Ignored on compilers that do not support GNU visibility arguments. See also `snippets.symbol_visibility_header()`[7] method to help with defining public API.

gui_app bool, default: false, deprecated since 0.56.0

When set to true flags this target as a GUI application on platforms where this makes a difference, deprecated since 0.56.0, use `win_subsystem` instead.

implicit_include_directories bool, default: true, since 0.42.0

Controls whether Meson adds the current source and build directories to the include path

include_directories array[inc | str]

one or more objects created with the include_directories function, or (since 0.50.0) strings, which will be transparently expanded to include directory objects

install bool, default: false

When set to true, this executable should be installed.

install_dir str

override install directory for this file. If the value is a relative path, it will be considered relative the `prefix` option. For example, if you want to install plugins into a subdir, you'd use something like this: `install_dir : get_option('libdir') / 'projectnam-1.0'`.

install_mode array[str | int], since 0.47.0

Specify the file mode in symbolic format and optionally the owner/uid and group/gid for the installed files.

See the `install_mode` kwarg of install_data for more information.

install_rpath str

A string to set the target's rpath to after install (but not before that). On Windows, this argument has no effect.

install_tag str, since 0.60.0

A string used by the `meson install-tags` command to install only a subset of the files. By default all build targets have the tag `runtime` except for static libraries that have the `devel` tag.

java_resources structured_src, since 0.62.0

Resources to be added to the jar

link_args array[str]

Flags to use during linking. You can use UNI-style flags here for all platforms.

link_depends str | file | custom_tgt | custom_idx

Strings, files, or custom targets the link step depends on such as a symbol visibility map. The purpose is to automatically trigger a r-link (but not a r-compile) of the target when this file changes.

link_language str, since 0.51.0

Makes the linker for this target be for the specified language. It is generally unnecessary to set this, as Meson will detect the right linker to use in most cases. There are only two cases where this is needed. One, your main function in an executable is not in the language Meson picked, or second you want to force a library to use only one ABI.

(broken until 0.55.0)

link_whole array[lib | custom_tgt | custom_idx], since 0.40.0

Links all contents of the given static libraries whether they are used or not, equivalent to the -Wl-whol-archive` argument flag of GCC, or the '/WHOLEARCHIVE' MSVC linker option. This allows the linked target to r-export symbols from all objects in the static libraries.

(since 0.41.0) If passed an array that array will be flattened.

(since 0.51.0) This argument also accepts outputs produced by custom targets. The user must ensure that the output is a library in the correct format.

link_with array[lib | custom_tgt | custom_idx]

One or more shared or static libraries (built by this project) that this target should be linked with. (since 0.41.0) If passed an array that array will be flattened. (since 0.51.0) The arguments can also be custom targets. In this case Meson will assume that merely adding the output file in the linker command line is sufficient to make linking work. If this is not sufficient, then the build system writer must write all other steps manually.

main_class str

Main class for running the built jar

name_prefix str | array[void]

The string that will be used as the prefix for the target output filename by overriding the default (only used for libraries). By default this is `lib` on all platforms and compilers, except for MSVC shared libraries where it is omitted to follow convention, and Cygwin shared libraries where it is `cyg`.

Set this to `[]`, or omit the keyword argument for the default behaviour.

name_suffix str | array[void]

The string that will be used as the extension for the target by overriding the default. By default on Windows this is `exe` for executables and on other platforms it is omitted.

For shared libraries, the default value is `dylib` on macOS, `dll` on Windows, and `so` everywhere else. For static libraries, it is `a` everywhere. By convention MSVC static libraries use the `lib` suffix, but we use `a` to avoid a potential name clash with shared libraries which also generate import libraries with a `lib` suffix.

Set this to `[]`, or omit the keyword argument for the default behaviour.

native bool, default: false

Controls whether the target is compiled for the build or host machines.

objects array[extracted_obj | file | str]

List of object files that should be linked in this target.

Since 1.1.0 this can include generated files in addition to object files that you don't have source to or that object files produced by other build targets. In earlier release, generated object files had to be placed in `sources`.

override_options array[str] | dict[str | bool | int | array[str]], since 0.40.0

takes an array of strings in the same format as `project`'s `default_options` overriding the values of these options for this target only. (since 1.2.0): A dictionary may now be passed.

rust_crate_type str, deprecated since 1.3.0, since 0.42.0

Set the specific type of rust crate to compile (when compiling rust).

If the target is an executable this defaults to "bin", the only allowed value.

If it is a static_library it defaults to "lib", and may be "lib", "staticlib", or "rlib". If "lib" then Rustc will pick a default, "staticlib" means a C ABI library, "rlib" means a Rust ABI.

If it is a shared_library it defaults to "lib", and may be "lib", "dylib", "cdylib", or "pro-macro". If "lib" then Rustc will pick a default, "cdylib" means a C ABI library, "dylib" means a Rust ABI, and "pro-macro" is a special rust procedural macro crate.

"pro-macro" is new in 0.62.0.

Since 1.3.0 this is deprecated and replaced by "rust_abi" keyword argument. `proc_macro` crates are now handled by the `rust.proc_macro()`[8] method.

rust_dependency_map dict[str], since 1.2.0

On rust targets this allows giving custom names to the crates that are linked into the target. For example, passing a dependency map of `{ 'gtk4': 'gtk' }` has the same effect of writing `gtk.package = "gtk4"` in the `dependencies` section of a Cargo.toml file, or `extern crate gtk4 as gtk` inside Rust code.

Since 1.10.0, the keys can be either crate names or target names.

sources str | file | custom_tgt | custom_idx | generated_list | structured_src

Additional source files. Same as the source varargs.

vala_args array[str | file]

Compiler flags for Vala. Unlike other languages this may contain Files

vala_gir str

If set, generates a GIR file with the given name. If this is unset then no GIR file will be generated.

vala_header str

On Vala targets, this provides a way to override the name of the generated C compatible header for targets that generate them.

If it is not set the default will be calculated from the target's name.

vala_vapi str

On Vala targets, this provides a way to override the name of the generated VAPI file.

If it is not set the default will be calculated from the target's name.

win_subsystem str, default: 'console', since 0.56.0

Specifies the subsystem type to use on the Windows platform. Typical values include `console` for text mode programs and `windows` for gui apps. The value can also contain version specification such as `windows,6.0`. See MSDN documentation[9] for the full list.

 

join_paths()

SYNOPSIS

str join_paths(part...)

since 0.36.0

DESCRIPTION

Joins the given strings into a file system path segment. For example `join_paths('foo', 'bar')` results in `foo/bar`. If any one of the individual segments is an absolute path, all segments before it are dropped. That means that `join_paths('foo', '/bar')` returns `/bar`.

(since 0.49.0) Using the `/` operator on strings is equivalent to calling join_paths.

# res1 and res2 will have identical values
res1 = join_paths(foo, bar)
res2 = foo / bar

VARARGS

part str, 1...N times

The path parts to join.

WARNINGS

Don't use join_paths for sources in library and executable. You should use files instead.

 

library()

SYNOPSIS

lib library(

target_name,
source...,
<lang>_args:,
<lang>_pch:,
<lang>_shared_args:,
<lang>_static_args:,
build_by_default: true,
build_rpath:,
build_subdir:,
d_debug:,
d_import_dirs:,
d_module_versions:,
d_unittest: false,
darwin_versions:,
dependencies:,
extra_files:,
gnu_symbol_visibility:,
gui_app: false,
implicit_include_directories: true,
include_directories:,
install: false,
install_dir:,
install_mode:,
install_rpath:,
install_tag:,
link_args:,
link_depends:,
link_language:,
link_whole:,
link_with:,
name_prefix:,
name_suffix:,
native: false,
objects:,
override_options:,
pic:,
prelink:,
rust_abi:,
rust_crate_type:,
rust_dependency_map:,
shortname:,
sources:,
soversion:,
vala_args:,
vala_gir:,
vala_header:,
vala_shared_args:,
vala_static_args:,
vala_vapi:,
version:,
vs_module_defs:,
win_subsystem: 'console',

)

DESCRIPTION

Builds a library that is either static, shared or both depending on the value of `default_library` user option[25]. You should use this instead of shared_library, static_library or both_libraries most of the time. This allows you to toggle your entire project (including subprojects) from shared to static with only one option. This option applies to libraries being built internal to the entire project. For external dependencies, the default library type preferred is shared. This can be adapted on a per library basis using the dependency `static` keyword.

The keyword arguments for this are the same as for build_target

POSARGS

target_name str, required

The unique name of the build target

VARARGS

source str | file | custom_tgt | custom_idx | generated_list, 0...N times

Input source to compile. The following types are supported:

- Strings relative to the current source directory
- file objects defined in any preceding build file
- The return value of configur-time generators such as configure_file
- The return value of buil-time generators such as custom_target or generator.process

These input files can be sources, objects, libraries, or any other file. Meson will automatically categorize them based on the extension and use them accordingly. For instance, sources (`.c`, `.cpp`, `.vala`, `.rs`, etc) will be compiled and objects (`.o`, `.obj`) and libraries (`.so`, `.dll`, etc) will be linked.

With the Ninja backend, Meson will create a buil-time orde-only dependency[3] on all generated input files, including unknown files. This is needed to bootstrap the generation of the real dependencies in the depfile[4] generated by your compiler to determine when to rebuild sources. Ninja relies on this dependency file for all input files, generated and no-generated. The behavior is similar for other backends.

KWARGS

<lang>_args array[str]

compiler flags to use for the given language; eg: `cpp_args` for C++

<lang>_pch str

precompiled header file to use for the given language

<lang>_shared_args array[str], since 1.3.0

Arguments that are only passed to a shared library

<lang>_static_args array[str], since 1.3.0

Arguments that are only passed to a static library

build_by_default bool, default: true, since 0.38.0

Causes, when set to `true`, to have this target be built by default. This means it will be built when `meson compile` is called without any arguments. The default value is `true` for all built target types.

build_rpath str, since 0.42.0

A string to add to target's rpath definition in the build dir, but which will be removed on install

build_subdir str, since 1.10.0

Places the build results in a subdirectory of the given name rather than directly into the build directory. This does not affect the install directory, which uses install_dir. This allows inserting a directory name into the build path, either when needed to use the build result while building other targets or as a way to support multiple targets with the same basename by using unique build_subdir values for each one. To prevent collisions within the build directory, build_subdir is not allowed to match a file or directory in the source directory, nor contain '..' to refer to the parent of the build directory.

d_debug array[str]

The D version identifiers[5] to add during the compilation of D source files.

d_import_dirs array[inc | str], since 0.62.0

the directories to add to the string search path (i.e. -J` switch for DMD). Must be inc objects or plain strings.

d_module_versions array[str | int]

List of module version identifiers set when compiling D sources.

d_unittest bool, default: false

When set to true, the D modules are compiled in debug mode.

darwin_versions str | int | array[str], since 0.48.0

Defines the `compatibility version` and `current version` for the dylib on macOS. If an array is specified, it must be either zero, one, or two elements. If only one element is specified or if it's not an array the specified value will be used for setting both compatibility version and current version. If unspecified, the `soversion` will be used as per the aforementioned rules.

dependencies array[dep]

one or more dependency objects created with dependency or compiler.find_library (for external deps) or declare_dependency (for deps built by the project)

extra_files str | file

Not used for the build itself but are shown as source files in IDEs that group files by targets (such as Visual Studio).

These may only be static sources.

gnu_symbol_visibility str, since 0.48.0

Specifies how symbols should be exported, see e.g the GCC Wiki[6] for more information. This value can either be an empty string or one of `default`, `internal`, `hidden`, `protected` or `inlineshidden`, which is the same as `hidden` but also includes things like C++ implicit constructors as specified in the GCC manual. Ignored on compilers that do not support GNU visibility arguments. See also `snippets.symbol_visibility_header()`[7] method to help with defining public API.

gui_app bool, default: false, deprecated since 0.56.0

When set to true flags this target as a GUI application on platforms where this makes a difference, deprecated since 0.56.0, use `win_subsystem` instead.

implicit_include_directories bool, default: true, since 0.42.0

Controls whether Meson adds the current source and build directories to the include path

include_directories array[inc | str]

one or more objects created with the include_directories function, or (since 0.50.0) strings, which will be transparently expanded to include directory objects

install bool, default: false

When set to true, this executable should be installed.

install_dir str

override install directory for this file. If the value is a relative path, it will be considered relative the `prefix` option. For example, if you want to install plugins into a subdir, you'd use something like this: `install_dir : get_option('libdir') / 'projectnam-1.0'`.

install_mode array[str | int], since 0.47.0

Specify the file mode in symbolic format and optionally the owner/uid and group/gid for the installed files.

See the `install_mode` kwarg of install_data for more information.

install_rpath str

A string to set the target's rpath to after install (but not before that). On Windows, this argument has no effect.

install_tag str, since 0.60.0

A string used by the `meson install-tags` command to install only a subset of the files. By default all build targets have the tag `runtime` except for static libraries that have the `devel` tag.

link_args array[str]

Flags to use during linking. You can use UNI-style flags here for all platforms.

link_depends str | file | custom_tgt | custom_idx

Strings, files, or custom targets the link step depends on such as a symbol visibility map. The purpose is to automatically trigger a r-link (but not a r-compile) of the target when this file changes.

link_language str, since 0.51.0

Makes the linker for this target be for the specified language. It is generally unnecessary to set this, as Meson will detect the right linker to use in most cases. There are only two cases where this is needed. One, your main function in an executable is not in the language Meson picked, or second you want to force a library to use only one ABI.

(broken until 0.55.0)

link_whole array[lib | custom_tgt | custom_idx], since 0.40.0

Links all contents of the given static libraries whether they are used or not, equivalent to the -Wl-whol-archive` argument flag of GCC, or the '/WHOLEARCHIVE' MSVC linker option. This allows the linked target to r-export symbols from all objects in the static libraries.

(since 0.41.0) If passed an array that array will be flattened.

(since 0.51.0) This argument also accepts outputs produced by custom targets. The user must ensure that the output is a library in the correct format.

link_with array[lib | custom_tgt | custom_idx]

One or more shared or static libraries (built by this project) that this target should be linked with. (since 0.41.0) If passed an array that array will be flattened. (since 0.51.0) The arguments can also be custom targets. In this case Meson will assume that merely adding the output file in the linker command line is sufficient to make linking work. If this is not sufficient, then the build system writer must write all other steps manually.

name_prefix str | array[void]

The string that will be used as the prefix for the target output filename by overriding the default (only used for libraries). By default this is `lib` on all platforms and compilers, except for MSVC shared libraries where it is omitted to follow convention, and Cygwin shared libraries where it is `cyg`.

Set this to `[]`, or omit the keyword argument for the default behaviour.

name_suffix str | array[void]

The string that will be used as the extension for the target by overriding the default. By default on Windows this is `exe` for executables and on other platforms it is omitted.

For shared libraries, the default value is `dylib` on macOS, `dll` on Windows, and `so` everywhere else. For static libraries, it is `a` everywhere. By convention MSVC static libraries use the `lib` suffix, but we use `a` to avoid a potential name clash with shared libraries which also generate import libraries with a `lib` suffix.

Set this to `[]`, or omit the keyword argument for the default behaviour.

native bool, default: false

Controls whether the target is compiled for the build or host machines.

objects array[extracted_obj | file | str]

List of object files that should be linked in this target.

Since 1.1.0 this can include generated files in addition to object files that you don't have source to or that object files produced by other build targets. In earlier release, generated object files had to be placed in `sources`.

override_options array[str] | dict[str | bool | int | array[str]], since 0.40.0

takes an array of strings in the same format as `project`'s `default_options` overriding the values of these options for this target only. (since 1.2.0): A dictionary may now be passed.

pic bool, since 0.36.0

Builds the library as positional independent code (so it can be linked into a shared library). This option has no effect on Windows and OS X since it doesn't make sense on Windows and PIC cannot be disabled on OS X.

prelink bool, since 0.57.0

If `true` the object files in the target will be prelinked, meaning that it will contain only one prelinked object file rather than the individual object files.

rust_abi str, since 1.3.0

Set the specific ABI to compile (when compiling rust).- 'rust' (default): Create a "rlib" or "dylib" crate depending on the library type being build.
- 'c': Create a "cdylib" or "staticlib" crate depending on the library type being build.

rust_crate_type str, deprecated since 1.3.0, since 0.42.0

Set the specific type of rust crate to compile (when compiling rust).

If the target is an executable this defaults to "bin", the only allowed value.

If it is a static_library it defaults to "lib", and may be "lib", "staticlib", or "rlib". If "lib" then Rustc will pick a default, "staticlib" means a C ABI library, "rlib" means a Rust ABI.

If it is a shared_library it defaults to "lib", and may be "lib", "dylib", "cdylib", or "pro-macro". If "lib" then Rustc will pick a default, "cdylib" means a C ABI library, "dylib" means a Rust ABI, and "pro-macro" is a special rust procedural macro crate.

"pro-macro" is new in 0.62.0.

Since 1.3.0 this is deprecated and replaced by "rust_abi" keyword argument. `proc_macro` crates are now handled by the `rust.proc_macro()`[8] method.

rust_dependency_map dict[str], since 1.2.0

On rust targets this allows giving custom names to the crates that are linked into the target. For example, passing a dependency map of `{ 'gtk4': 'gtk' }` has the same effect of writing `gtk.package = "gtk4"` in the `dependencies` section of a Cargo.toml file, or `extern crate gtk4 as gtk` inside Rust code.

Since 1.10.0, the keys can be either crate names or target names.

shortname str, since 1.10.0

A string specifying a DLL name fitting to 8.3 limit on OS/2 of this shared library.

sources str | file | custom_tgt | custom_idx | generated_list | structured_src

Additional source files. Same as the source varargs.

soversion str | int

A string or integer specifying the soversion of this shared library, such as `0`. On Linux and Windows this is used to set the soversion (or equivalent) in the filename. For example, if `soversion` is `4`, a Windows DLL will be called `fo-4.dll` and one of the aliases of the Linux shared library would be `libfoo.so.4`. If this is not specified, the first part of `version` is used instead (see below). For example, if `version` is `3.6.0` and `soversion` is not defined, it is set to `3`.

vala_args array[str | file]

Compiler flags for Vala. Unlike other languages this may contain Files

vala_gir str

If set, generates a GIR file with the given name. If this is unset then no GIR file will be generated.

vala_header str

On Vala targets, this provides a way to override the name of the generated C compatible header for targets that generate them.

If it is not set the default will be calculated from the target's name.

vala_shared_args array[str | file], since 1.3.0

Arguments that are only passed to a shared library Like `vala_args`, files is allowed in addition to string

vala_static_args array[str | file], since 1.3.0

Arguments that are only passed to a static library Like `vala_args`, files is allowed in addition to string

vala_vapi str

On Vala targets, this provides a way to override the name of the generated VAPI file.

If it is not set the default will be calculated from the target's name.

version str

A string specifying the version of this shared library, such as `1.1.0`. On Linux and OS X, this is used to set the shared library version in the filename, such as `libfoo.so.1.1.0` and `libfoo.1.1.0.dylib`. If this is not specified, `soversion` is used instead (see above).

vs_module_defs str | file | custom_tgt | custom_idx

Specify a Microsoft module definition file for controlling symbol exports, etc., on platforms where that is possible (e.g. Windows).

(Since 1.3.0) custom_idx are supported

win_subsystem str, default: 'console', since 0.56.0

Specifies the subsystem type to use on the Windows platform. Typical values include `console` for text mode programs and `windows` for gui apps. The value can also contain version specification such as `windows,6.0`. See MSDN documentation[9] for the full list.

WARNINGS

using <lang>_shared_args and/or <lang>_static_args may lead to much higher compilation times with both_library, as object files cannot be shared between the static and shared targets. It is guaranteed to not duplicate the build if these arguments are empty arrays

 

message()

SYNOPSIS

void message(text, more_text...)

DESCRIPTION

This function prints its argument to stdout.

POSARGS

text str | int | bool | array[str | int | bool] | dict[str | int | bool], required

The message to print.

VARARGS

more_text str | int | bool | array[str | int | bool] | dict[str | int | bool], 0...N times, since 0.54.0

Additional text that will be printed separated by spaces.

 

project()

SYNOPSIS

void project(

project_name,
language...,
default_options:,
license:,
license_files:,
meson_version:,
subproject_dir: 'subprojects',
version:,

)

DESCRIPTION

The first function called in each project, to initialize Meson.

The first argument to this function must be a string defining the name of this project.

The project name can be any string you want, it's not used for anything except descriptive purposes. However since it is written to e.g. the dependency manifest is usually makes sense to have it be the same as the project tarball or pk-config name. So for example you would probably want to use the name _libfoobar_ instead of _The Foobar Library_.

It may be followed by the array of programming languages that the project uses.

(since 0.40.0) The array of languages is optional.

These languages may be used both for `native: false` (the default) (host machine) targets and for `native: true` (build machine) targets. (since 0.56.0) The build machine compilers for the specified languages are not required.

Supported values for languages are `c`, `cpp` (for `C++`), `cuda`, `cython`, `d`, `objc`, `objcpp`, `fortran`, `java`, `cs` (for `C#`), `swift`, `nasm`, `masm`, `linearasm`, `vala` and `rust`.

POSARGS

project_name str, required

The name of the project.

VARARGS

language str, 0...N times

The languages that Meson should initialize.

KWARGS

default_options array[str] | dict[str | bool | int | array[str]]

Accepts strings in the form `key=value` which have the same format as options to `meson configure`. For example to set the default project type you would set this: `default_options : 'buildtype=debugoptimized']`. Note that these settings are only used when running Meson for the first time.

Note that some options can override the default behavior; for example, using `c_args` here means that the `CFLAGS` environment variable is not used. Consider using add_project_arguments() instead.

Also note that not all options are taken into account when building as a subproject, and the exact set of options that are pe-subproject has increased over time; for more information, see [core options[18] and compiler options[26].

(since 1.2.0): A dictionary may now be passed.

license str | array[str]

Takes a string or array of strings describing the license(s) the code is under.

This should be an SPDX license expression[27], using the standardized license identifier from the SPDX license list[28]. Usually this would be something like `license : 'GP-2.-o-later'`. If there are multiple licenses you can use the `AND` and `OR` operators to join them: `license : 'Apach-2.0 OR GP-2.0'`.

For backwards compatibility reasons you can also pass an array of licenses here. This is not recommended, as it is ambiguous: `license : ['Apach-2.0', 'GP-2.-only']` instead use an SPDX expression: `license : 'Apach-2.0 OR GP-2.-only'`, which makes it clear that the license mean OR, not AND.

Note that the text is informal and is only written to the dependency manifest. Meson does not do any license validation, you are responsible for verifying that you abide by all licensing terms. You can access the value in your Meson build files with `meson.project_license()`.

license_files str | array[str], since 1.1.0

Takes a string or array of strings with the paths to the license file(s) the code is under.

This enhances the value of the `license` kwarg by allowing to specify both the short license name and the full license text. Usually this would be something like `license_files: ['COPYING']`.

Note that the files are informal and are only installed with the dependency manifest. Meson does not do any license validation, you are responsible for verifying that you abide by all licensing terms. You can access the value in your Meson build files with meson.project_license_files.

meson_version str

Takes a string describing which Meson version the project requires. Usually something like `>=0.28.0`.

subproject_dir str, default: 'subprojects'

Specifies the top level directory name that holds Meson subprojects. This is only meant as a compatibility option for existing code bases that house their embedded source code in a custom directory. All new projects should not set this but instead use the default value. It should be noted that this keyword argument is ignored inside subprojects. There can be only one subproject dir and it is set in the top level Meson file.

version str | file

A free form string describing the version of this project. You can access the value in your Meson build files with meson.project_version. (Since 0.57.0) this can also be a file object pointing to a file that contains exactly one line of text.

 

range()

SYNOPSIS

range range([start], [stop], [step])

since 0.58.0

DESCRIPTION

Return an opaque object that can be only be used in `foreach` statements.

<pre><code class="languag-meson">range range(int <b>stop</b>) range range(int <b>start</b>, int <b>stop</b>[, int <b>step</b>])</code></pre>

- `start` must be integer greater or equal to 0. Defaults to 0.
- `stop` must be integer greater or equal to `start`.
- `step` must be integer greater or equal to 1. Defaults to 1.

It cause the `foreach` loop to be called with the value from `start` included to `stop` excluded with an increment of `step` after each loop.

OPTARGS

start int, default: 0

The start of the range

stop int

The end of the range

step int, default: 1

The loop increment

EXAMPLE

# Loop 15 times with i from 0 to 14 included.
foreach i : range(15)

  ...
endforeach

The range object can also be assigned to a variable and indexed.

r = range(5, 10, 2)
assert(r[2] == 9)

 

run_command()

SYNOPSIS

runresult run_command(

command...,
capture: true,
check: false,
env:,

)

DESCRIPTION

Runs the command specified in positional arguments. `command` can be a string, or the output of find_program, files or configure_file, or a compiler object.

Returns a runresult object containing the result of the invocation. The command is run from an unspecified directory, and Meson will set three environment variables `MESON_SOURCE_ROOT`, `MESON_BUILD_ROOT` and `MESON_SUBDIR` that specify the source directory, build directory and subdirectory the target was defined in, respectively.

See also External commands[29].

VARARGS

command str | file | external_program, 0...N times

The command to execute during the setup process.

KWARGS

capture bool, default: true, since 0.47.0

If `true`, any output generated on stdout will be captured and returned by the `.stdout()` method. If it is false, then `.stdout()` will return an empty string.

check bool, default: false, since 0.47.0

If `true`, the exit status code of the command will be checked, and the configuration will fail if it is no-zero. Note that the default value will be `true` in future releases.

env env | array[str] | dict[str], since 0.50.0

environment variables to set, such as `['NAME1=value1', 'NAME2=value2']`, or an env object which allows more sophisticated environment juggling. (Since 0.52.0) A dictionary is also accepted.

 

run_target()

SYNOPSIS

run_tgt run_target(target_name, command:, depends:, env:)

DESCRIPTION

This function creates a new to-level target that runs a specified command with the specified arguments. Like all to-level targets, this integrates with the selected backend. For instance, you can run it as `meson compile target_name`. Note that a run target produces no output as far as Meson is concerned. It is only meant for tasks such as running a code formatter or flashing an external device's firmware with a built file.

The command is run from an unspecified directory, and Meson will set three environment variables `MESON_SOURCE_ROOT`, `MESON_BUILD_ROOT` and `MESON_SUBDIR` that specify the source directory, build directory and subdirectory the target was defined in, respectively.

Since 0.57.0 The template strings passed to `command` keyword arguments accept the following special substitutions:- `@SOURCE_ROOT@`: the path to the root of the source tree. Depending on the backend, this may be an absolute or a relative to current workdir path.
- `@BUILD_ROOT@`: the path to the root of the build tree. Depending on the backend, this may be an absolute or a relative to current workdir path.
- `@CURRENT_SOURCE_DIR@` Since 0.57.1: this is the directory where the currently processed meson.build is located in. Depending on the backend, this may be an absolute or a relative to current workdir path.

POSARGS

target_name str, required

The name of the run target

KWARGS

command array[exe| external_program | custom_tgt | file | str]

An array containing the command to run and the arguments to pass to it. Each array element may be a string or a target. For instance, passing the return value of executable as the first item will run that executable, or passing a string as the first item will find that command in `PATH` and run it.

depends array[build_tgt | custom_tgt | custom_idx]

An array of targets that this target depends on but which are not listed in the command array (because, for example, the script does file globbing internally, custom_idx was not possible as a type between 0.60 and 1.4.0).

env env | array[str] | dict[str], since 0.57.0

environment variables to set, such as `{'NAME1': 'value1', 'NAME2': 'value2'}` or `['NAME1=value1', 'NAME2=value2']`, or an env object which allows more sophisticated environment juggling.

 

set_variable()

SYNOPSIS

void set_variable(variable_name, value)

DESCRIPTION

Assigns a value to the given variable name. Calling `set_variable('foo', bar)` is equivalent to `foo = bar`.

(since 0.46.1) The `value` parameter can be an array type.

POSARGS

variable_name str, required

The name of the variable to set

value any, required

The value to set the variable to

 

shared_library()

SYNOPSIS

lib shared_library(

target_name,
source...,
<lang>_args:,
<lang>_pch:,
build_by_default: true,
build_rpath:,
build_subdir:,
d_debug:,
d_import_dirs:,
d_module_versions:,
d_unittest: false,
darwin_versions:,
dependencies:,
extra_files:,
gnu_symbol_visibility:,
gui_app: false,
implicit_include_directories: true,
include_directories:,
install: false,
install_dir:,
install_mode:,
install_rpath:,
install_tag:,
link_args:,
link_depends:,
link_language:,
link_whole:,
link_with:,
name_prefix:,
name_suffix:,
native: false,
objects:,
override_options:,
rust_abi:,
rust_crate_type:,
rust_dependency_map:,
shortname:,
sources:,
soversion:,
vala_args:,
vala_gir:,
vala_header:,
vala_vapi:,
version:,
vs_module_defs:,
win_subsystem: 'console',

)

DESCRIPTION

Builds a shared library with the given sources.

POSARGS

target_name str, required

The unique name of the build target

VARARGS

source str | file | custom_tgt | custom_idx | generated_list, 0...N times

Input source to compile. The following types are supported:

- Strings relative to the current source directory
- file objects defined in any preceding build file
- The return value of configur-time generators such as configure_file
- The return value of buil-time generators such as custom_target or generator.process

These input files can be sources, objects, libraries, or any other file. Meson will automatically categorize them based on the extension and use them accordingly. For instance, sources (`.c`, `.cpp`, `.vala`, `.rs`, etc) will be compiled and objects (`.o`, `.obj`) and libraries (`.so`, `.dll`, etc) will be linked.

With the Ninja backend, Meson will create a buil-time orde-only dependency[3] on all generated input files, including unknown files. This is needed to bootstrap the generation of the real dependencies in the depfile[4] generated by your compiler to determine when to rebuild sources. Ninja relies on this dependency file for all input files, generated and no-generated. The behavior is similar for other backends.

KWARGS

<lang>_args array[str]

compiler flags to use for the given language; eg: `cpp_args` for C++

<lang>_pch str

precompiled header file to use for the given language

build_by_default bool, default: true, since 0.38.0

Causes, when set to `true`, to have this target be built by default. This means it will be built when `meson compile` is called without any arguments. The default value is `true` for all built target types.

build_rpath str, since 0.42.0

A string to add to target's rpath definition in the build dir, but which will be removed on install

build_subdir str, since 1.10.0

Places the build results in a subdirectory of the given name rather than directly into the build directory. This does not affect the install directory, which uses install_dir. This allows inserting a directory name into the build path, either when needed to use the build result while building other targets or as a way to support multiple targets with the same basename by using unique build_subdir values for each one. To prevent collisions within the build directory, build_subdir is not allowed to match a file or directory in the source directory, nor contain '..' to refer to the parent of the build directory.

d_debug array[str]

The D version identifiers[5] to add during the compilation of D source files.

d_import_dirs array[inc | str], since 0.62.0

the directories to add to the string search path (i.e. -J` switch for DMD). Must be inc objects or plain strings.

d_module_versions array[str | int]

List of module version identifiers set when compiling D sources.

d_unittest bool, default: false

When set to true, the D modules are compiled in debug mode.

darwin_versions str | int | array[str], since 0.48.0

Defines the `compatibility version` and `current version` for the dylib on macOS. If an array is specified, it must be either zero, one, or two elements. If only one element is specified or if it's not an array the specified value will be used for setting both compatibility version and current version. If unspecified, the `soversion` will be used as per the aforementioned rules.

dependencies array[dep]

one or more dependency objects created with dependency or compiler.find_library (for external deps) or declare_dependency (for deps built by the project)

extra_files str | file

Not used for the build itself but are shown as source files in IDEs that group files by targets (such as Visual Studio).

These may only be static sources.

gnu_symbol_visibility str, since 0.48.0

Specifies how symbols should be exported, see e.g the GCC Wiki[6] for more information. This value can either be an empty string or one of `default`, `internal`, `hidden`, `protected` or `inlineshidden`, which is the same as `hidden` but also includes things like C++ implicit constructors as specified in the GCC manual. Ignored on compilers that do not support GNU visibility arguments. See also `snippets.symbol_visibility_header()`[7] method to help with defining public API.

gui_app bool, default: false, deprecated since 0.56.0

When set to true flags this target as a GUI application on platforms where this makes a difference, deprecated since 0.56.0, use `win_subsystem` instead.

implicit_include_directories bool, default: true, since 0.42.0

Controls whether Meson adds the current source and build directories to the include path

include_directories array[inc | str]

one or more objects created with the include_directories function, or (since 0.50.0) strings, which will be transparently expanded to include directory objects

install bool, default: false

When set to true, this executable should be installed.

install_dir str

override install directory for this file. If the value is a relative path, it will be considered relative the `prefix` option. For example, if you want to install plugins into a subdir, you'd use something like this: `install_dir : get_option('libdir') / 'projectnam-1.0'`.

install_mode array[str | int], since 0.47.0

Specify the file mode in symbolic format and optionally the owner/uid and group/gid for the installed files.

See the `install_mode` kwarg of install_data for more information.

install_rpath str

A string to set the target's rpath to after install (but not before that). On Windows, this argument has no effect.

install_tag str, since 0.60.0

A string used by the `meson install-tags` command to install only a subset of the files. By default all build targets have the tag `runtime` except for static libraries that have the `devel` tag.

link_args array[str]

Flags to use during linking. You can use UNI-style flags here for all platforms.

link_depends str | file | custom_tgt | custom_idx

Strings, files, or custom targets the link step depends on such as a symbol visibility map. The purpose is to automatically trigger a r-link (but not a r-compile) of the target when this file changes.

link_language str, since 0.51.0

Makes the linker for this target be for the specified language. It is generally unnecessary to set this, as Meson will detect the right linker to use in most cases. There are only two cases where this is needed. One, your main function in an executable is not in the language Meson picked, or second you want to force a library to use only one ABI.

(broken until 0.55.0)

link_whole array[lib | custom_tgt | custom_idx], since 0.40.0

Links all contents of the given static libraries whether they are used or not, equivalent to the -Wl-whol-archive` argument flag of GCC, or the '/WHOLEARCHIVE' MSVC linker option. This allows the linked target to r-export symbols from all objects in the static libraries.

(since 0.41.0) If passed an array that array will be flattened.

(since 0.51.0) This argument also accepts outputs produced by custom targets. The user must ensure that the output is a library in the correct format.

link_with array[lib | custom_tgt | custom_idx]

One or more shared or static libraries (built by this project) that this target should be linked with. (since 0.41.0) If passed an array that array will be flattened. (since 0.51.0) The arguments can also be custom targets. In this case Meson will assume that merely adding the output file in the linker command line is sufficient to make linking work. If this is not sufficient, then the build system writer must write all other steps manually.

name_prefix str | array[void]

The string that will be used as the prefix for the target output filename by overriding the default (only used for libraries). By default this is `lib` on all platforms and compilers, except for MSVC shared libraries where it is omitted to follow convention, and Cygwin shared libraries where it is `cyg`.

Set this to `[]`, or omit the keyword argument for the default behaviour.

name_suffix str | array[void]

The string that will be used as the extension for the target by overriding the default. By default on Windows this is `exe` for executables and on other platforms it is omitted.

For shared libraries, the default value is `dylib` on macOS, `dll` on Windows, and `so` everywhere else. For static libraries, it is `a` everywhere. By convention MSVC static libraries use the `lib` suffix, but we use `a` to avoid a potential name clash with shared libraries which also generate import libraries with a `lib` suffix.

Set this to `[]`, or omit the keyword argument for the default behaviour.

native bool, default: false

Controls whether the target is compiled for the build or host machines.

objects array[extracted_obj | file | str]

List of object files that should be linked in this target.

Since 1.1.0 this can include generated files in addition to object files that you don't have source to or that object files produced by other build targets. In earlier release, generated object files had to be placed in `sources`.

override_options array[str] | dict[str | bool | int | array[str]], since 0.40.0

takes an array of strings in the same format as `project`'s `default_options` overriding the values of these options for this target only. (since 1.2.0): A dictionary may now be passed.

rust_abi str, since 1.3.0

Set the specific ABI to compile (when compiling rust).- 'rust' (default): Create a "dylib" crate.
- 'c': Create a "cdylib" crate.

rust_crate_type str, deprecated since 1.3.0, since 0.42.0

Set the specific type of rust crate to compile (when compiling rust).

If the target is an executable this defaults to "bin", the only allowed value.

If it is a static_library it defaults to "lib", and may be "lib", "staticlib", or "rlib". If "lib" then Rustc will pick a default, "staticlib" means a C ABI library, "rlib" means a Rust ABI.

If it is a shared_library it defaults to "lib", and may be "lib", "dylib", "cdylib", or "pro-macro". If "lib" then Rustc will pick a default, "cdylib" means a C ABI library, "dylib" means a Rust ABI, and "pro-macro" is a special rust procedural macro crate.

"pro-macro" is new in 0.62.0.

Since 1.3.0 this is deprecated and replaced by "rust_abi" keyword argument. `proc_macro` crates are now handled by the `rust.proc_macro()`[8] method.

rust_dependency_map dict[str], since 1.2.0

On rust targets this allows giving custom names to the crates that are linked into the target. For example, passing a dependency map of `{ 'gtk4': 'gtk' }` has the same effect of writing `gtk.package = "gtk4"` in the `dependencies` section of a Cargo.toml file, or `extern crate gtk4 as gtk` inside Rust code.

Since 1.10.0, the keys can be either crate names or target names.

shortname str, since 1.10.0

A string specifying a DLL name fitting to 8.3 limit on OS/2 of this shared library.

sources str | file | custom_tgt | custom_idx | generated_list | structured_src

Additional source files. Same as the source varargs.

soversion str | int

A string or integer specifying the soversion of this shared library, such as `0`. On Linux and Windows this is used to set the soversion (or equivalent) in the filename. For example, if `soversion` is `4`, a Windows DLL will be called `fo-4.dll` and one of the aliases of the Linux shared library would be `libfoo.so.4`. If this is not specified, the first part of `version` is used instead (see below). For example, if `version` is `3.6.0` and `soversion` is not defined, it is set to `3`.

vala_args array[str | file]

Compiler flags for Vala. Unlike other languages this may contain Files

vala_gir str

If set, generates a GIR file with the given name. If this is unset then no GIR file will be generated.

vala_header str

On Vala targets, this provides a way to override the name of the generated C compatible header for targets that generate them.

If it is not set the default will be calculated from the target's name.

vala_vapi str

On Vala targets, this provides a way to override the name of the generated VAPI file.

If it is not set the default will be calculated from the target's name.

version str

A string specifying the version of this shared library, such as `1.1.0`. On Linux and OS X, this is used to set the shared library version in the filename, such as `libfoo.so.1.1.0` and `libfoo.1.1.0.dylib`. If this is not specified, `soversion` is used instead (see above).

vs_module_defs str | file | custom_tgt | custom_idx

Specify a Microsoft module definition file for controlling symbol exports, etc., on platforms where that is possible (e.g. Windows).

(Since 1.3.0) custom_idx are supported

win_subsystem str, default: 'console', since 0.56.0

Specifies the subsystem type to use on the Windows platform. Typical values include `console` for text mode programs and `windows` for gui apps. The value can also contain version specification such as `windows,6.0`. See MSDN documentation[9] for the full list.

 

shared_module()

SYNOPSIS

build_tgt shared_module(

target_name,
source...,
<lang>_args:,
<lang>_pch:,
build_by_default: true,
build_rpath:,
build_subdir:,
d_debug:,
d_import_dirs:,
d_module_versions:,
d_unittest: false,
dependencies:,
extra_files:,
gnu_symbol_visibility:,
gui_app: false,
implicit_include_directories: true,
include_directories:,
install: false,
install_dir:,
install_mode:,
install_rpath:,
install_tag:,
link_args:,
link_depends:,
link_language:,
link_whole:,
link_with:,
name_prefix:,
name_suffix:,
native: false,
objects:,
override_options:,
rust_abi:,
rust_crate_type:,
rust_dependency_map:,
sources:,
vala_args:,
vala_gir:,
vala_header:,
vala_vapi:,
vs_module_defs:,
win_subsystem: 'console',

)

since 0.37.0

DESCRIPTION

Builds a shared module with the given sources.

This is useful for building modules that will be `dlopen()`ed and hence may contain undefined symbols that will be provided by the library that is loading it.

If you want the shared module to be able to refer to functions and variables defined in the executable it is loaded by, you will need to set the `export_dynamic` argument of the executable to `true`.

POSARGS

target_name str, required

The unique name of the build target

VARARGS

source str | file | custom_tgt | custom_idx | generated_list, 0...N times

Input source to compile. The following types are supported:

- Strings relative to the current source directory
- file objects defined in any preceding build file
- The return value of configur-time generators such as configure_file
- The return value of buil-time generators such as custom_target or generator.process

These input files can be sources, objects, libraries, or any other file. Meson will automatically categorize them based on the extension and use them accordingly. For instance, sources (`.c`, `.cpp`, `.vala`, `.rs`, etc) will be compiled and objects (`.o`, `.obj`) and libraries (`.so`, `.dll`, etc) will be linked.

With the Ninja backend, Meson will create a buil-time orde-only dependency[3] on all generated input files, including unknown files. This is needed to bootstrap the generation of the real dependencies in the depfile[4] generated by your compiler to determine when to rebuild sources. Ninja relies on this dependency file for all input files, generated and no-generated. The behavior is similar for other backends.

KWARGS

<lang>_args array[str]

compiler flags to use for the given language; eg: `cpp_args` for C++

<lang>_pch str

precompiled header file to use for the given language

build_by_default bool, default: true, since 0.38.0

Causes, when set to `true`, to have this target be built by default. This means it will be built when `meson compile` is called without any arguments. The default value is `true` for all built target types.

build_rpath str, since 0.42.0

A string to add to target's rpath definition in the build dir, but which will be removed on install

build_subdir str, since 1.10.0

Places the build results in a subdirectory of the given name rather than directly into the build directory. This does not affect the install directory, which uses install_dir. This allows inserting a directory name into the build path, either when needed to use the build result while building other targets or as a way to support multiple targets with the same basename by using unique build_subdir values for each one. To prevent collisions within the build directory, build_subdir is not allowed to match a file or directory in the source directory, nor contain '..' to refer to the parent of the build directory.

d_debug array[str]

The D version identifiers[5] to add during the compilation of D source files.

d_import_dirs array[inc | str], since 0.62.0

the directories to add to the string search path (i.e. -J` switch for DMD). Must be inc objects or plain strings.

d_module_versions array[str | int]

List of module version identifiers set when compiling D sources.

d_unittest bool, default: false

When set to true, the D modules are compiled in debug mode.

dependencies array[dep]

one or more dependency objects created with dependency or compiler.find_library (for external deps) or declare_dependency (for deps built by the project)

extra_files str | file

Not used for the build itself but are shown as source files in IDEs that group files by targets (such as Visual Studio).

These may only be static sources.

gnu_symbol_visibility str, since 0.48.0

Specifies how symbols should be exported, see e.g the GCC Wiki[6] for more information. This value can either be an empty string or one of `default`, `internal`, `hidden`, `protected` or `inlineshidden`, which is the same as `hidden` but also includes things like C++ implicit constructors as specified in the GCC manual. Ignored on compilers that do not support GNU visibility arguments. See also `snippets.symbol_visibility_header()`[7] method to help with defining public API.

gui_app bool, default: false, deprecated since 0.56.0

When set to true flags this target as a GUI application on platforms where this makes a difference, deprecated since 0.56.0, use `win_subsystem` instead.

implicit_include_directories bool, default: true, since 0.42.0

Controls whether Meson adds the current source and build directories to the include path

include_directories array[inc | str]

one or more objects created with the include_directories function, or (since 0.50.0) strings, which will be transparently expanded to include directory objects

install bool, default: false

When set to true, this executable should be installed.

install_dir str

override install directory for this file. If the value is a relative path, it will be considered relative the `prefix` option. For example, if you want to install plugins into a subdir, you'd use something like this: `install_dir : get_option('libdir') / 'projectnam-1.0'`.

install_mode array[str | int], since 0.47.0

Specify the file mode in symbolic format and optionally the owner/uid and group/gid for the installed files.

See the `install_mode` kwarg of install_data for more information.

install_rpath str

A string to set the target's rpath to after install (but not before that). On Windows, this argument has no effect.

install_tag str, since 0.60.0

A string used by the `meson install-tags` command to install only a subset of the files. By default all build targets have the tag `runtime` except for static libraries that have the `devel` tag.

link_args array[str]

Flags to use during linking. You can use UNI-style flags here for all platforms.

link_depends str | file | custom_tgt | custom_idx

Strings, files, or custom targets the link step depends on such as a symbol visibility map. The purpose is to automatically trigger a r-link (but not a r-compile) of the target when this file changes.

link_language str, since 0.51.0

Makes the linker for this target be for the specified language. It is generally unnecessary to set this, as Meson will detect the right linker to use in most cases. There are only two cases where this is needed. One, your main function in an executable is not in the language Meson picked, or second you want to force a library to use only one ABI.

(broken until 0.55.0)

link_whole array[lib | custom_tgt | custom_idx], since 0.40.0

Links all contents of the given static libraries whether they are used or not, equivalent to the -Wl-whol-archive` argument flag of GCC, or the '/WHOLEARCHIVE' MSVC linker option. This allows the linked target to r-export symbols from all objects in the static libraries.

(since 0.41.0) If passed an array that array will be flattened.

(since 0.51.0) This argument also accepts outputs produced by custom targets. The user must ensure that the output is a library in the correct format.

link_with array[lib | custom_tgt | custom_idx]

One or more shared or static libraries (built by this project) that this target should be linked with. (since 0.41.0) If passed an array that array will be flattened. (since 0.51.0) The arguments can also be custom targets. In this case Meson will assume that merely adding the output file in the linker command line is sufficient to make linking work. If this is not sufficient, then the build system writer must write all other steps manually.

name_prefix str | array[void]

The string that will be used as the prefix for the target output filename by overriding the default (only used for libraries). By default this is `lib` on all platforms and compilers, except for MSVC shared libraries where it is omitted to follow convention, and Cygwin shared libraries where it is `cyg`.

Set this to `[]`, or omit the keyword argument for the default behaviour.

name_suffix str | array[void]

The string that will be used as the extension for the target by overriding the default. By default on Windows this is `exe` for executables and on other platforms it is omitted.

For shared libraries, the default value is `dylib` on macOS, `dll` on Windows, and `so` everywhere else. For static libraries, it is `a` everywhere. By convention MSVC static libraries use the `lib` suffix, but we use `a` to avoid a potential name clash with shared libraries which also generate import libraries with a `lib` suffix.

Set this to `[]`, or omit the keyword argument for the default behaviour.

native bool, default: false

Controls whether the target is compiled for the build or host machines.

objects array[extracted_obj | file | str]

List of object files that should be linked in this target.

Since 1.1.0 this can include generated files in addition to object files that you don't have source to or that object files produced by other build targets. In earlier release, generated object files had to be placed in `sources`.

override_options array[str] | dict[str | bool | int | array[str]], since 0.40.0

takes an array of strings in the same format as `project`'s `default_options` overriding the values of these options for this target only. (since 1.2.0): A dictionary may now be passed.

rust_abi str, since 1.3.0

Set the specific ABI to compile (when compiling rust).- 'rust' (default): Create a "dylib" crate.
- 'c': Create a "cdylib" crate.

rust_crate_type str, deprecated since 1.3.0, since 0.42.0

Set the specific type of rust crate to compile (when compiling rust).

If the target is an executable this defaults to "bin", the only allowed value.

If it is a static_library it defaults to "lib", and may be "lib", "staticlib", or "rlib". If "lib" then Rustc will pick a default, "staticlib" means a C ABI library, "rlib" means a Rust ABI.

If it is a shared_library it defaults to "lib", and may be "lib", "dylib", "cdylib", or "pro-macro". If "lib" then Rustc will pick a default, "cdylib" means a C ABI library, "dylib" means a Rust ABI, and "pro-macro" is a special rust procedural macro crate.

"pro-macro" is new in 0.62.0.

Since 1.3.0 this is deprecated and replaced by "rust_abi" keyword argument. `proc_macro` crates are now handled by the `rust.proc_macro()`[8] method.

rust_dependency_map dict[str], since 1.2.0

On rust targets this allows giving custom names to the crates that are linked into the target. For example, passing a dependency map of `{ 'gtk4': 'gtk' }` has the same effect of writing `gtk.package = "gtk4"` in the `dependencies` section of a Cargo.toml file, or `extern crate gtk4 as gtk` inside Rust code.

Since 1.10.0, the keys can be either crate names or target names.

sources str | file | custom_tgt | custom_idx | generated_list | structured_src

Additional source files. Same as the source varargs.

vala_args array[str | file]

Compiler flags for Vala. Unlike other languages this may contain Files

vala_gir str

If set, generates a GIR file with the given name. If this is unset then no GIR file will be generated.

vala_header str

On Vala targets, this provides a way to override the name of the generated C compatible header for targets that generate them.

If it is not set the default will be calculated from the target's name.

vala_vapi str

On Vala targets, this provides a way to override the name of the generated VAPI file.

If it is not set the default will be calculated from the target's name.

vs_module_defs str | file | custom_tgt | custom_idx, since 0.52.0

Specify a Microsoft module definition file for controlling symbol exports, etc., on platforms where that is possible (e.g. Windows).

(Since 1.3.0) custom_idx are supported

win_subsystem str, default: 'console', since 0.56.0

Specifies the subsystem type to use on the Windows platform. Typical values include `console` for text mode programs and `windows` for gui apps. The value can also contain version specification such as `windows,6.0`. See MSDN documentation[9] for the full list.

NOTES

*Linking to a shared module on platforms other than Android is deprecated, and will be an error in the future*. It was previously allowed because it was the only way to have a share-librar-like target that contained references to undefined symbols. However, since 0.40.0, the `override_options:` build_target keyword argument can be used to create such a shared_library by passing `override_options: 'b_lundef=false'`. Shared modules have other characteristics that make them incompatible with linking, such as a lack of SONAME. On macOS and iOS, linking to shared modules is disallowed by the linker, so we disallow it at configure time. On Android, if a shared module `foo` uses symbols from another shared module `bar`, `foo` must also be linked to `bar`. Hence, linking one shared module to another will always be allowed when building for Android.

 

static_library()

SYNOPSIS

lib static_library(

target_name,
source...,
<lang>_args:,
<lang>_pch:,
build_by_default: true,
build_rpath:,
build_subdir:,
d_debug:,
d_import_dirs:,
d_module_versions:,
d_unittest: false,
dependencies:,
extra_files:,
gnu_symbol_visibility:,
gui_app: false,
implicit_include_directories: true,
include_directories:,
install: false,
install_dir:,
install_mode:,
install_rpath:,
install_tag:,
link_args:,
link_depends:,
link_language:,
link_whole:,
link_with:,
name_prefix:,
name_suffix:,
native: false,
objects:,
override_options:,
pic:,
prelink:,
rust_abi:,
rust_crate_type:,
rust_dependency_map:,
sources:,
vala_args:,
vala_gir:,
vala_header:,
vala_vapi:,
win_subsystem: 'console',

)

DESCRIPTION

Builds a static library with the given sources.

POSARGS

target_name str, required

The unique name of the build target

VARARGS

source str | file | custom_tgt | custom_idx | generated_list, 0...N times

Input source to compile. The following types are supported:

- Strings relative to the current source directory
- file objects defined in any preceding build file
- The return value of configur-time generators such as configure_file
- The return value of buil-time generators such as custom_target or generator.process

These input files can be sources, objects, libraries, or any other file. Meson will automatically categorize them based on the extension and use them accordingly. For instance, sources (`.c`, `.cpp`, `.vala`, `.rs`, etc) will be compiled and objects (`.o`, `.obj`) and libraries (`.so`, `.dll`, etc) will be linked.

With the Ninja backend, Meson will create a buil-time orde-only dependency[3] on all generated input files, including unknown files. This is needed to bootstrap the generation of the real dependencies in the depfile[4] generated by your compiler to determine when to rebuild sources. Ninja relies on this dependency file for all input files, generated and no-generated. The behavior is similar for other backends.

KWARGS

<lang>_args array[str]

compiler flags to use for the given language; eg: `cpp_args` for C++

<lang>_pch str

precompiled header file to use for the given language

build_by_default bool, default: true, since 0.38.0

Causes, when set to `true`, to have this target be built by default. This means it will be built when `meson compile` is called without any arguments. The default value is `true` for all built target types.

build_rpath str, since 0.42.0

A string to add to target's rpath definition in the build dir, but which will be removed on install

build_subdir str, since 1.10.0

Places the build results in a subdirectory of the given name rather than directly into the build directory. This does not affect the install directory, which uses install_dir. This allows inserting a directory name into the build path, either when needed to use the build result while building other targets or as a way to support multiple targets with the same basename by using unique build_subdir values for each one. To prevent collisions within the build directory, build_subdir is not allowed to match a file or directory in the source directory, nor contain '..' to refer to the parent of the build directory.

d_debug array[str]

The D version identifiers[5] to add during the compilation of D source files.

d_import_dirs array[inc | str], since 0.62.0

the directories to add to the string search path (i.e. -J` switch for DMD). Must be inc objects or plain strings.

d_module_versions array[str | int]

List of module version identifiers set when compiling D sources.

d_unittest bool, default: false

When set to true, the D modules are compiled in debug mode.

dependencies array[dep]

one or more dependency objects created with dependency or compiler.find_library (for external deps) or declare_dependency (for deps built by the project)

extra_files str | file

Not used for the build itself but are shown as source files in IDEs that group files by targets (such as Visual Studio).

These may only be static sources.

gnu_symbol_visibility str, since 0.48.0

Specifies how symbols should be exported, see e.g the GCC Wiki[6] for more information. This value can either be an empty string or one of `default`, `internal`, `hidden`, `protected` or `inlineshidden`, which is the same as `hidden` but also includes things like C++ implicit constructors as specified in the GCC manual. Ignored on compilers that do not support GNU visibility arguments. See also `snippets.symbol_visibility_header()`[7] method to help with defining public API.

gui_app bool, default: false, deprecated since 0.56.0

When set to true flags this target as a GUI application on platforms where this makes a difference, deprecated since 0.56.0, use `win_subsystem` instead.

implicit_include_directories bool, default: true, since 0.42.0

Controls whether Meson adds the current source and build directories to the include path

include_directories array[inc | str]

one or more objects created with the include_directories function, or (since 0.50.0) strings, which will be transparently expanded to include directory objects

install bool, default: false

When set to true, this executable should be installed.

install_dir str

override install directory for this file. If the value is a relative path, it will be considered relative the `prefix` option. For example, if you want to install plugins into a subdir, you'd use something like this: `install_dir : get_option('libdir') / 'projectnam-1.0'`.

install_mode array[str | int], since 0.47.0

Specify the file mode in symbolic format and optionally the owner/uid and group/gid for the installed files.

See the `install_mode` kwarg of install_data for more information.

install_rpath str

A string to set the target's rpath to after install (but not before that). On Windows, this argument has no effect.

install_tag str, since 0.60.0

A string used by the `meson install-tags` command to install only a subset of the files. By default all build targets have the tag `runtime` except for static libraries that have the `devel` tag.

link_args array[str]

Flags to use during linking. You can use UNI-style flags here for all platforms.

link_depends str | file | custom_tgt | custom_idx

Strings, files, or custom targets the link step depends on such as a symbol visibility map. The purpose is to automatically trigger a r-link (but not a r-compile) of the target when this file changes.

link_language str, since 0.51.0

Makes the linker for this target be for the specified language. It is generally unnecessary to set this, as Meson will detect the right linker to use in most cases. There are only two cases where this is needed. One, your main function in an executable is not in the language Meson picked, or second you want to force a library to use only one ABI.

(broken until 0.55.0)

link_whole array[lib | custom_tgt | custom_idx], since 0.40.0

Links all contents of the given static libraries whether they are used or not, equivalent to the -Wl-whol-archive` argument flag of GCC, or the '/WHOLEARCHIVE' MSVC linker option. This allows the linked target to r-export symbols from all objects in the static libraries.

(since 0.41.0) If passed an array that array will be flattened.

(since 0.51.0) This argument also accepts outputs produced by custom targets. The user must ensure that the output is a library in the correct format.

link_with array[lib | custom_tgt | custom_idx]

One or more shared or static libraries (built by this project) that this target should be linked with. (since 0.41.0) If passed an array that array will be flattened. (since 0.51.0) The arguments can also be custom targets. In this case Meson will assume that merely adding the output file in the linker command line is sufficient to make linking work. If this is not sufficient, then the build system writer must write all other steps manually.

name_prefix str | array[void]

The string that will be used as the prefix for the target output filename by overriding the default (only used for libraries). By default this is `lib` on all platforms and compilers, except for MSVC shared libraries where it is omitted to follow convention, and Cygwin shared libraries where it is `cyg`.

Set this to `[]`, or omit the keyword argument for the default behaviour.

name_suffix str | array[void]

The string that will be used as the extension for the target by overriding the default. By default on Windows this is `exe` for executables and on other platforms it is omitted.

For shared libraries, the default value is `dylib` on macOS, `dll` on Windows, and `so` everywhere else. For static libraries, it is `a` everywhere. By convention MSVC static libraries use the `lib` suffix, but we use `a` to avoid a potential name clash with shared libraries which also generate import libraries with a `lib` suffix.

Set this to `[]`, or omit the keyword argument for the default behaviour.

native bool, default: false

Controls whether the target is compiled for the build or host machines.

objects array[extracted_obj | file | str]

List of object files that should be linked in this target.

Since 1.1.0 this can include generated files in addition to object files that you don't have source to or that object files produced by other build targets. In earlier release, generated object files had to be placed in `sources`.

override_options array[str] | dict[str | bool | int | array[str]], since 0.40.0

takes an array of strings in the same format as `project`'s `default_options` overriding the values of these options for this target only. (since 1.2.0): A dictionary may now be passed.

pic bool, since 0.36.0

Builds the library as positional independent code (so it can be linked into a shared library). This option has no effect on Windows and OS X since it doesn't make sense on Windows and PIC cannot be disabled on OS X.

prelink bool, since 0.57.0

If `true` the object files in the target will be prelinked, meaning that it will contain only one prelinked object file rather than the individual object files.

rust_abi str, since 1.3.0

Set the specific ABI to compile (when compiling rust).- 'rust' (default): Create a "rlib" crate.
- 'c': Create a "staticlib" crate.

rust_crate_type str, deprecated since 1.3.0, since 0.42.0

Set the specific type of rust crate to compile (when compiling rust).

If the target is an executable this defaults to "bin", the only allowed value.

If it is a static_library it defaults to "lib", and may be "lib", "staticlib", or "rlib". If "lib" then Rustc will pick a default, "staticlib" means a C ABI library, "rlib" means a Rust ABI.

If it is a shared_library it defaults to "lib", and may be "lib", "dylib", "cdylib", or "pro-macro". If "lib" then Rustc will pick a default, "cdylib" means a C ABI library, "dylib" means a Rust ABI, and "pro-macro" is a special rust procedural macro crate.

"pro-macro" is new in 0.62.0.

Since 1.3.0 this is deprecated and replaced by "rust_abi" keyword argument. `proc_macro` crates are now handled by the `rust.proc_macro()`[8] method.

rust_dependency_map dict[str], since 1.2.0

On rust targets this allows giving custom names to the crates that are linked into the target. For example, passing a dependency map of `{ 'gtk4': 'gtk' }` has the same effect of writing `gtk.package = "gtk4"` in the `dependencies` section of a Cargo.toml file, or `extern crate gtk4 as gtk` inside Rust code.

Since 1.10.0, the keys can be either crate names or target names.

sources str | file | custom_tgt | custom_idx | generated_list | structured_src

Additional source files. Same as the source varargs.

vala_args array[str | file]

Compiler flags for Vala. Unlike other languages this may contain Files

vala_gir str

If set, generates a GIR file with the given name. If this is unset then no GIR file will be generated.

vala_header str

On Vala targets, this provides a way to override the name of the generated C compatible header for targets that generate them.

If it is not set the default will be calculated from the target's name.

vala_vapi str

On Vala targets, this provides a way to override the name of the generated VAPI file.

If it is not set the default will be calculated from the target's name.

win_subsystem str, default: 'console', since 0.56.0

Specifies the subsystem type to use on the Windows platform. Typical values include `console` for text mode programs and `windows` for gui apps. The value can also contain version specification such as `windows,6.0`. See MSDN documentation[9] for the full list.

 

structured_sources()

SYNOPSIS

structured_src structured_sources(root, [additional])

since 0.62.0

DESCRIPTION

Create a StructuredSource object, which is opaque and may be passed as a source to any build_target (including static_library, shared_library, executable, etc.). This is useful for languages like Rust, which use the filesystem layout to determine import names. This is only allowed in Rust targets, and cannot be mixed with non structured inputs.

POSARGS

root array[str | file | custom_tgt | custom_idx | generated_list], required

Sources to put at the root of the generated structure

OPTARGS

additional dict[str | file | custom_tgt | custom_idx | generated_list]

Additional sources, where the key is the directory under the root to place the values

 

subdir()

SYNOPSIS

void subdir(dir_name, if_found:)

DESCRIPTION

Enters the specified subdirectory and executes the `meson.build` file in it. Once that is done, it returns and execution continues on the line following this `subdir()` command. Variables defined in that `meson.build` file are then available for use in later parts of the current build file and in all subsequent build files executed with `subdir()`.

Note that this means that each `meson.build` file in a source tree can and must only be executed once.

POSARGS

dir_name str, required

Directory relative to the current `meson.build` to enter.

Cannot contain `..`

KWARGS

if_found array[dep], since 0.44.0

Only enter the subdir if all dep.found methods return `true`.

 

subdir_done()

SYNOPSIS

void subdir_done()

since 0.46.0

DESCRIPTION

Stops further interpretation of the Meson script file from the point of the invocation. All steps executed up to this point are valid and will be executed by Meson. This means that all targets defined before the call of subdir_done will be built.

If the current script was called by `subdir`, the execution returns to the calling directory and continues as if the script had reached the end. If the current script is the top level script, Meson configures the project as defined up to this point.

EXAMPLE

project('example exit', 'cpp')
executable('exe1', 'exe1.cpp')
subdir_done()
executable('exe2', 'exe2.cpp')

The executable `exe1` will be built, while the executable `exe2` is not built.

 

subproject()

SYNOPSIS

subproject subproject(

subproject_name,
default_options:,
required: true,
version:,

)

DESCRIPTION

Takes the project specified in the positional argument and brings that in the current build specification by returning a subproject object. Subprojects must always be placed inside the `subprojects` directory at the top source directory. So for example a subproject called `foo` must be located in `${MESON_SOURCE_ROOT}/subprojects/foo`.

- `default_options` (since 0.37.0): an array of default option values that override those set in the subproject's `meson.options` (like `default_options` in `project`, they only have effect when Meson is run for the first time, and command line arguments override any default options in build files). (since 0.54.0): `default_library` buil-in option can also be overridden. (since 1.2.0): A dictionary may be passed instead of array.
- `version`: works just like the same as in `dependency`. It specifies what version the subproject should be, as an example `>=1.0.1`
- `required` (since 0.48.0): By default, `required` is `true` and Meson will abort if the subproject could not be setup. You can set this to `false` and then use the `.found()` method on the subproject object. You may also pass the value of a `feature`[0] option, same as dependency.

Note that you can use the returned subproject object to access any variable in the subproject. However, if you want to use a dependency object from inside a subproject, an easier way is to use the `fallback:` keyword argument to dependency.

See additional documentation[30].

POSARGS

subproject_name str, required

Name of the subproject. The subproject must exist in the `subprojects` directory (or the directory specified in the `subproject_dir` of project) as a directory or wrap file.

KWARGS

default_options array[str] | dict[str | bool | int | array[str]], since 0.37.0

An array of default option values that override those set in the subproject's `meson.options` (like `default_options` in project, they only have effect when Meson is run for the first time, and command line arguments override any default options in build files). (since 0.54.0): `default_library` buil-in option can also be overridden. (since 1.2.0): A dictionary may now be passed.

required bool | feature, default: true, since 0.48.0

Works just the same as in dependency.

version str

Works just like the same as in dependency. It specifies what version the subproject should be, as an example `>=1.0.1`.

 

summary()

SYNOPSIS

void summary(

key_or_dict,
[value],
bool_yn: false,
list_sep:,
section:,

)

since 0.53.0

DESCRIPTION

This function is used to summarize build configuration at the end of the build process. This function provides a way for projects (and subprojects) to report this information in a clear way.

The content is a series of key/value pairs grouped into sections. If the section keyword argument is omitted, those key/value pairs are implicitly grouped into a section with no title. key/value pairs can optionally be grouped into a dictionary, but keep in mind that dictionaries do not guarantee ordering. `key` must be string, `value` can be:

- an integer, boolean or string
- since 0.57.0 an external program or a dependency
- since 0.58.0 a feature option
- an array of those.

Instead of calling summary as `summary(key, value)`, it is also possible to directly pass a dictionary to the summary function, as seen in the example below.

`summary()` can be called multiple times as long as the same section/key pair doesn't appear twice. All sections will be collected and printed at the end of the configuration in the same order as they have been called.

POSARGS

key_or_dict str | dict[str | bool | int | dep | external_program | array[str | bool | int | dep | external_program]], required

The name of the new entry, or a dict containing multiple entries. If a dict is passed it is equivalent to calling summary() once for each ke-value pair. Keep in mind that dictionaries do not guarantee ordering.

OPTARGS

value str | bool | int | dep | external_program | array[str | bool | int | dep | external_program]

The value to print for the `key`. Only valid if `key_or_dict` is a str.

KWARGS

bool_yn bool, default: false

Convert bool values to yes and no

list_sep str, since 0.54.0

The separator to use when printing array values in this summary. If no separator is given, each array item will be printed on its own line.

section str

The section to put this summary information under. If the section keyword argument is omitted, key/value pairs are implicitly grouped into a section with no title.

EXAMPLE

Example `meson.build`:

project('My Project', version : '1.0')
summary({'bindir': get_option('bindir'),

        'libdir': get_option('libdir'),

        'datadir': get_option('datadir'),

        }, section: 'Directories')
summary({'Some boolean': false,

        'Another boolean': true,

        'Some string': 'Hello World',

        'An array': ['string', 1, true],

        }, section: 'Configuration')

Output:

My Project 1.0

  Directories

    prefix         : /opt/gnome

    bindir         : bin

    libdir         : lib/x86_6-linu-gnu

    datadir        : share

  Configuration

    Some boolean   : False

    Another boolean: True

    Some string    : Hello World

    An array        : string

                     1

                     True

 

test()

SYNOPSIS

void test(

name,
executable,
args:,
depends:,
env:,
is_parallel: true,
priority: 0,
protocol: 'exitcode',
should_fail: false,
suite:,
timeout: 30,
verbose: false,
workdir:,

)

DESCRIPTION

Defines a test to run with the test harness. Takes two positional arguments, the first is the name of the test and the second is the executable to run. The executable can be an exe object returned by executable or an external_program object] returned by find_program.

(since 0.55.0) When cross compiling, if an exe_wrapper is needed and defined the environment variable `MESON_EXE_WRAPPER` will be set to the string value of that wrapper (implementation detail: using `mesonlib.join_args`). Test scripts may use this to run cross built binaries. If your test needs `MESON_EXE_WRAPPER` in cross build situations it is your responsibility to return code 77 to tell the harness to report "skip".

By default, environment variable `MALLOC_PERTURB_`[31] is automatically set by `meson test` to a random value between 1..255. This can help find memory leaks on configurations using glibc, including with no-GCC compilers. However, this can have a performance impact, and may fail a test due to external libraries whose internals are out of the user's control. To check if this feature is causing an expected runtime crash, disable the feature by temporarily setting environment variable `MALLOC_PERTURB_=0`. While it's preferable to only temporarily disable this check, if a project requires permanent disabling of this check in meson.build do like:

nomalloc = environment({'MALLOC_PERTURB_': '0'})

test(..., env: nomalloc, ...)

By default, the environment variables `ASAN_OPTIONS`, `UBSAN_OPTIONS`, and `MSAN_OPTIONS` are set to enable aborting on detected violations and to give a backtrace. To suppress this, `ASAN_OPTIONS`, `UBSAN_OPTIONS`, or `MSAN_OPTIONS` can be set in the environment.

In addition to running individual executables as test cases, `test()` can also be used to invoke an external test harness. In this case, it is best to use `verbose: true` (since 0.62.0) and, if supported by the external harness, `protocol: 'tap'` (since 0.50.0). This will ensure that Meson logs each subtest as it runs, instead of including the whole log at the end of the run.

Defined tests can be run in a backen-agnostic way by calling `meson test` inside the build dir, or by using backen-specific commands, such as `ninja test` or `msbuild RUN_TESTS.vcxproj`.

POSARGS

name str, required

The unique test id

executable exe | jar | external_program | file | custom_tgt | custom_idx, required

The program to execute. (Since 1.4.0) A CustomTarget is also accepted.

KWARGS

args array[str | file | tgt | external_program]

Arguments to pass to the executable

depends array[build_tgt | custom_tgt], since 0.46.0

specifies that this test depends on the specified target(s), even though it does not take any of them as a command line argument. This is meant for cases where test finds those targets internally, e.g. plugins or globbing. Those targets are built before test is executed even if they have `build_by_default : false`.

env env | array[str] | dict[str]

environment variables to set, such as `['NAME1=value1', 'NAME2=value2']`, or an env object which allows more sophisticated environment juggling. (Since 0.52.0) A dictionary is also accepted.

is_parallel bool, default: true

when false, specifies that no other test must be running at the same time as this test

priority int, default: 0, since 0.52.0

specifies the priority of a test. Tests with a higher priority are started before tests with a lower priority. The starting order of tests with identical priorities is implementatio-defined. The default priority is 0, negative numbers are permitted.

protocol str, default: 'exitcode', since 0.50.0

specifies how the test results are parsed and can be one of `exitcode`, `tap`, or `gtest`. For more information about test harness protocol read Unit Tests[1]. The following values are accepted:

- `exitcode`: the executable's exit code is used by the test harness to record the outcome of the test).
- `tap`: Test Anything Protocol[2].
- `gtest` (since 0.55.0): for Google Tests.
- `rust` (since 0.56.0): for native rust tests

should_fail bool, default: false

when true the test is considered passed if the executable returns a no-zero return value (i.e. reports an error)

suite str | array[str]

`'label'` (or array of labels `['label1', 'label2']`) attached to this test. The suite name is qualified by a (sub)project name resulting in `(sub)project_name:label`. In the case of an array of strings, the suite names will be `(sub)project_name:label1`, `(sub)project_name:label2`, etc.

timeout int, default: 30

the amount of seconds the test is allowed to run, a test that exceeds its time limit is always considered failed, defaults to 30 seconds. Since 0.57 if timeout is `<= 0` the test has infinite duration, in previous versions of Meson the test would fail with a timeout immediately.

verbose bool, default: false, since 0.62.0

if true, forces the test results to be logged as if -verbose` was passed to `meson test`.

workdir str

absolute path that will be used as the working directory for the test

 

unset_variable()

SYNOPSIS

void unset_variable(varname)

since 0.60.0

DESCRIPTION

Unsets a variable. Referencing a variable which has been unset is an error until it has been set again.

POSARGS

varname str, required

The variable to unset.

 

vcs_tag()

SYNOPSIS

custom_tgt vcs_tag(

command:,
fallback: [[meson.project_version]],
input:,
install: false,
install_dir:,
install_mode:,
install_tag:,
output:,
replace_string: '@VCS_TAG@',

)

DESCRIPTION

This command detects revision control commit information at build time and places it in the specified output file. This file is guaranteed to be up to date on every build. Keywords are similar to custom_target.

Meson will read the contents of `input`, substitute the `replace_string` with the detected revision number, and write the result to `output`. This method returns a custom_tgt object that (as usual) should be used to signal dependencies if other targets use the file outputted by this.

For example, if you generate a header with this and want to use that in a build target, you must add the return value to the sources of that build target. Without that, Meson will not know the order in which to build the targets.

If you desire more specific behavior than what this command provides, you should use custom_target.

KWARGS

command array[exe | external_program | custom_tgt | file | str]

The command to execute, see custom_target for details on how this command must be specified.

This parameter is optional. If it is absent, Meson will try its best to find a suitable default command.

(since 0.62.0) file is accepted.

(since 0.63.0) custom_tgt, exe, and external_program are accepted.

fallback str, default: [[meson.project_version]]

Version number to use when no revision control information is present, such as when building from a release tarball.

input str, required

File to modify (e.g. `version.c.in`).

install bool, default: false, since 1.7.0

When true, this generated file is installed during the install step, and `install_dir` must be set and not empty.

install_dir str, since 1.7.0

The subdirectory to install the generated file to (e.g. `share/myproject`).

install_mode array[str | int], since 1.7.0

Specify the file mode in symbolic format and optionally the owner/uid and group/gid for the installed files.

See the `install_mode` kwarg of install_data for more information.

install_tag str, since 1.7.0

A string used by the `meson install-tags` command to install only a subset of the files. By default the file has no install tag which means it is not being installed when -tags` argument is specified.

output str, required

File to write the results to (e.g. `version.c`).

replace_string str, default: '@VCS_TAG@'

String in the input file to substitute with the commit information.

 

warning()

SYNOPSIS

void warning(text, more_text...)

since 0.44.0

DESCRIPTION

This function prints its argument to stdout prefixed with WARNING:.

POSARGS

text str | int | bool | array[str | int | bool] | dict[str | int | bool], required

The message to print.

VARARGS

more_text str | int | bool | array[str | int | bool] | dict[str | int | bool], 0...N times, since 0.54.0

Additional text that will be printed separated by spaces.

 

array.contains()

SYNOPSIS

bool array.contains(item)

DESCRIPTION

Returns `true` if the array contains the object given as argument, `false` otherwise

POSARGS

item any, required

The item to check

 

array.flatten()

SYNOPSIS

array[any] array.flatten()

since 1.9.0

DESCRIPTION

Returns a flattened copy of the array, with all nested arrays removed.

 

array.get()

SYNOPSIS

any array.get(index, [fallback])

DESCRIPTION

returns the object at the given index, negative indices count from the back of the array, indexing out of bounds returns the `fallback` value (since 0.38.0) or, if it is not specified, causes a fatal error

POSARGS

index int, required

Index of the array position to query. Negative values start at the end of the array

OPTARGS

fallback any

Fallback value that is returned if the index is out of range.

 

array.length()

SYNOPSIS

int array.length()

DESCRIPTION

Returns the current size of the array.

 

array.slice()

SYNOPSIS

array[any] array.slice([start], [stop], step: 1)

since 1.10.0

DESCRIPTION

Return a selection of the elements of the array starting at index `start` and continuing with `step` size jumps until `stop`. Negative indices count from the back of the array. The step size cannot be zero, but may be negative. If it is negative, `start` and `stop` default to the end and beginning of the array, respectively. If `step` is positive, `start` defaults to 0 and `stop` defaults to the length of the array. Either both or none of `start` and `stop` must be provided to prevent ambiguity.

OPTARGS

start int

The lower bound of the slice

stop int

The upper bound of the slice

KWARGS

step int, default: 1

The step size

 

bool.to_int()

SYNOPSIS

int bool.to_int()

DESCRIPTION

Returns `1` if `true` and `0` if `false`

 

bool.to_string()

SYNOPSIS

str bool.to_string([true_str], [false_str])

DESCRIPTION

Returns the string `'true'` if the boolean is true or `'false'` otherwise. You can also pass it two strings as positional arguments to specify what to return for true/false. For instance, `bool.to_string('yes', 'no')` will return `yes` if the boolean is true and `no` if it is false.

OPTARGS

true_str str, default: 'true'

The string to return when the boolean is `true`

false_str str, default: 'false'

The string to return when the boolean is `false`

 

both_libs.get_shared_lib()

SYNOPSIS

lib both_libs.get_shared_lib()

DESCRIPTION

Returns the stored shared library

 

both_libs.get_static_lib()

SYNOPSIS

lib both_libs.get_static_lib()

DESCRIPTION

Returns the stored static library

 

build_machine.cpu()

SYNOPSIS

str build_machine.cpu()

DESCRIPTION

Returns a more specific CPU name, such as `i686`, `armv8l`, etc.

 

build_machine.cpu_family()

SYNOPSIS

str build_machine.cpu_family()

DESCRIPTION

Returns the CPU family name. This table[32] contains all known CPU families. These are guaranteed to continue working.

 

build_machine.endian()

SYNOPSIS

str build_machine.endian()

DESCRIPTION

returns `'big'` on bi-endian systems and `'little'` on littl-endian systems.

 

build_machine.kernel()

SYNOPSIS

str build_machine.kernel()

since 1.2.0

DESCRIPTION

Returns the name of the Operating System Kernel, such as `linux`, `xnu`, and `nt`. See here for more complete list[33] These are more specific than `system`. If this cannot be detected (for the build machine), or is not set in the cross file (for the host machine when cross compiling), calling this method is fatal.

 

build_machine.subsystem()

SYNOPSIS

str build_machine.subsystem()

since 1.2.0

DESCRIPTION

Returns the variant of the operating system, such as `ios` and `tvos`. See here for more complete list[32] These are more specific than `system`. If this cannot be detected (for the build machine), or is not set in the cross file (for the host machine when cross compiling), calling this method is fatal.

 

build_machine.system()

SYNOPSIS

str build_machine.system()

DESCRIPTION

Returns the operating system name. This table[34] Lists all of the currently known Operating System names, these are guaranteed to continue working.

 

build_tgt.extract_all_objects()

SYNOPSIS

extracted_obj build_tgt.extract_all_objects(

recursive: true,

)

DESCRIPTION

Acts the same as `extract_objects`, but returns all object files generated by this target.

By default only objects built for this target are returned to maintain backward compatibility with previous versions. The default value for the `recursive` kwarg will eventually be changed to `true` in a future version.

KWARGS

recursive bool, default: true, since 0.46.0

Also return objects passed to the `objects` argument of this target.

 

build_tgt.extract_objects()

SYNOPSIS

extracted_obj build_tgt.extract_objects(source...)

DESCRIPTION

Returns an opaque value representing the object files generated for those source files. This is typically used to take single object files and link them to unit tests or to compile some source files with custom flags. To use the object file(s) in another build target, use the `objects:` keyword argument to a build_target or declare_dependency, or include them in the command line of a custom_target.

VARARGS

source str | file, 1...N times

Source filenames for which the built objects should be extracted.

 

build_tgt.found()

SYNOPSIS

bool build_tgt.found()

since 0.59.0

DESCRIPTION

Always returns `true`. This function is meant to make executables objects feature compatible with external_program objects. This simplifies us-cases where an executable is used instead of an external_program.

 

build_tgt.full_path()

SYNOPSIS

str build_tgt.full_path()

DESCRIPTION

Returns a full path pointing to the result target file. NOTE: In most cases using the object itself will do the same job as this and will also allow Meson to setup inte-target dependencies correctly. Please file a bug if that doesn't work for you.

 

build_tgt.name()

SYNOPSIS

str build_tgt.name()

since 0.54.0

DESCRIPTION

Returns the name of the target.

 

build_tgt.path()

SYNOPSIS

str build_tgt.path()

deprecated since 0.59.0, since 0.59.0

DESCRIPTION

Does the exact same as build_tgt.full_path. NOTE: This function is solely kept for compatibility with external_program objects. It will be removed once the, also deprecated, corresponding `path()` function in the external_program object is removed.

 

build_tgt.private_dir_include()

SYNOPSIS

inc build_tgt.private_dir_include()

DESCRIPTION

Returns a value that works like include_directories, but points to the private directory of this target. Usually only needed if an another target needs to access some generated internal headers of this target.

 

build_tgt.vala_gir()

SYNOPSIS

file build_tgt.vala_gir()

since 1.10.0

DESCRIPTION

Returns a file object pointing to a GIR file generated by the vala compiler, if this target does not generate a GIR file then it is an error to call this method.

 

build_tgt.vala_header()

SYNOPSIS

file build_tgt.vala_header()

since 1.10.0

DESCRIPTION

Returns a file object pointing to a C compatible header generated by the vala compiler, if this target does not generate a vala header then it is an error to call this method.

 

build_tgt.vala_vapi()

SYNOPSIS

file build_tgt.vala_vapi()

since 1.10.0

DESCRIPTION

Returns a file object pointing to a VAPI header generated by the vala compiler, if this target does not generate a VAPI file then it is an error to call this method.

 

cfg_data.get()

SYNOPSIS

str | int | bool cfg_data.get(varname, [default_value])

since 0.38.0

DESCRIPTION

Returns the value of `varname`, if the value has not been set returns `default_value` if it is defined (since 0.38.0) and errors out if not

POSARGS

varname str, required

The name of the variable to query

OPTARGS

default_value str | int | bool

The default value to return when `varname` does not exist

 

cfg_data.get_unquoted()

SYNOPSIS

str | int | bool cfg_data.get_unquoted(varname, [default_value])

since 0.44.0

DESCRIPTION

Returns the value of `varname` but without surrounding double quotes (`"`). If the value has not been set returns `default_value` if it is defined and errors out if not.

POSARGS

varname str, required

The name of the variable to query

OPTARGS

default_value str | int | bool

The default value to return when `varname` does not exist

 

cfg_data.has()

SYNOPSIS

bool cfg_data.has(varname)

DESCRIPTION

returns `true` if the specified variable is set

POSARGS

varname str, required

The name of the variable to query

 

cfg_data.keys()

SYNOPSIS

array[str] cfg_data.keys()

since 0.57.0

DESCRIPTION

Returns an array of keys of the configuration data object.

You can iterate over this array with the `foreach` statement[35].

 

cfg_data.merge_from()

SYNOPSIS

void cfg_data.merge_from(other)

since 0.42.0

DESCRIPTION

Takes as argument a different configuration data object and copies all entries from that object to the current.

POSARGS

other cfg_data, required

The other cfg_data object to merge into this one.

 

cfg_data.set()

SYNOPSIS

void cfg_data.set(varname, value, description:)

DESCRIPTION

Sets a variable to a given value

POSARGS

varname str, required

The name of the variable to set

value str | int | bool, required

The value to set

KWARGS

description str

Message / Comment that will be written in the result file. The replacement assumes a file with C syntax. If your generated file is source code in some other language, you probably don't want to add a description field because it most likely will cause a syntax error.

 

cfg_data.set10()

SYNOPSIS

void cfg_data.set10(varname, value, description:)

DESCRIPTION

Is the same as cfg_data.set but the value is either `true` or `false` and will be written as 1 or 0, respectively

POSARGS

varname str, required

The name of the variable to set

value bool | int, required

The value to set as either `1` or `0`

Passing numbers was never intended to work, and since 0.62 it has been deprecated. It will be removed in a future version of Meson. If you need to pass numbers use the `.set` method.

KWARGS

description str

Message / Comment that will be written in the result file. The replacement assumes a file with C syntax. If your generated file is source code in some other language, you probably don't want to add a description field because it most likely will cause a syntax error.

WARNINGS

numeric values < 0 have the surprising behavior of being converted to `true`, values > 1 have the more expected but unintentional behavior of being interpreted as `true`.

 

cfg_data.set_quoted()

SYNOPSIS

void cfg_data.set_quoted(varname, value, description:)

DESCRIPTION

Is same as cfg_data.set but quotes the value in double quotes (`"`)

POSARGS

varname str, required

The name of the variable to set

value str | int | bool, required

The value to set

KWARGS

description str

Message / Comment that will be written in the result file. The replacement assumes a file with C syntax. If your generated file is source code in some other language, you probably don't want to add a description field because it most likely will cause a syntax error.

 

cmake.subproject_options()

SYNOPSIS

cmake_options cmake.subproject_options()

DESCRIPTION

Returns an empty `cmake_options` object.

 

cmake_options.add_cmake_defines()

SYNOPSIS

void cmake_options.add_cmake_defines(defines...)

DESCRIPTION

Add CMake defines (-D<VAR>=<VAL>`) to the CMake commandline

VARARGS

defines dict[str], 0...N times

A `key` `value` map of CMake defines to add (-D<key>=<val>`)

 

compiler.alignment()

SYNOPSIS

int compiler.alignment(typename, args:, dependencies:, prefix:)

DESCRIPTION

Returns the alignment of the specified type. For -like languages, For -like languages, the header `stddef.h` and `stdio.h` are included implicitly for native compilation, only `stddef.h` is included when cros-compiling.

POSARGS

typename str, required

The name of the type to check.

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

prefix str | array[str]

Used to add `#include`s and other things that are required for the symbol to be declared. Since 1.0.0 an array is accepted too. When an array is passed, the items are concatenated together separated by a newline. System definitions should be passed via compiler args (eg: `_GNU_SOURCE` is often required for some symbols to be exposed on Linux, and it should be passed via `args` keyword argument).

 

compiler.check_header()

SYNOPSIS

bool compiler.check_header(

header_name,
args:,
dependencies:,
include_directories:,
no_builtin_args: false,
prefix:,
required: false,

)

since 0.47.0

DESCRIPTION

Returns true if the specified header is usable with the specified prefix, dependencies, and arguments.

POSARGS

header_name str, required

The header to check.

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

no_builtin_args bool, default: false

When set to `true`, the compiler arguments controlled by buil-in configuration options are not added.

prefix str | array[str]

Used to add `#include`s and other things that are required for the symbol to be declared. Since 1.0.0 an array is accepted too. When an array is passed, the items are concatenated together separated by a newline. System definitions should be passed via compiler args (eg: `_GNU_SOURCE` is often required for some symbols to be exposed on Linux, and it should be passed via `args` keyword argument).

required bool | feature, default: false, since 0.50.0

When set to `true`, Meson will halt if the header check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

 

compiler.cmd_array()

SYNOPSIS

array[str] compiler.cmd_array()

DESCRIPTION

Returns an array containing the command(s) for the compiler.

 

compiler.compiles()

SYNOPSIS

bool compiler.compiles(

code,
args:,
dependencies:,
include_directories:,
name:,
no_builtin_args: false,
required: false,
werror: false,

)

DESCRIPTION

Returns true if the code compiles.

POSARGS

code str | file, required

The source code to check.

If a string is passed, the code is used directly. If a file object is passed, its content is used for the compiler check.

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

name str

The name to use for printing a message about the compiler check. If this keyword argument is not passed, no message will be printed about the check.

no_builtin_args bool, default: false

When set to `true`, the compiler arguments controlled by buil-in configuration options are not added.

required bool | feature, default: false, since 1.5.0

When set to `true`, Meson will halt if the check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

werror bool, default: false, since 1.3.0

When set to `true`, compiler warnings are treated as error.

 

compiler.compute_int()

SYNOPSIS

int compiler.compute_int(

expr,
args:,
dependencies:,
guess:,
high: 1024,
include_directories:,
low: -1024,
no_builtin_args: false,
prefix:,

)

since 0.40.0

DESCRIPTION

Computes the value of the given expression (as an example `1 + 2`). When cross compiling this is evaluated with an iterative algorithm, you can specify keyword arguments `low` (defaults to-1024), `high` (defaults to 1024) and `guess` to specify max and min values for the search and the value to try first. For -like languages, the header `stddef.h` and `stdio.h` are included implicitly for native compilation, only `stddef.h` is included when cros-compiling.

POSARGS

expr str, required

The expression to compute.

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

guess int

The value to try first.

high int, default: 1024

The max value.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

low int, default:-1024

The min value.

no_builtin_args bool, default: false

When set to `true`, the compiler arguments controlled by buil-in configuration options are not added.

prefix str | array[str]

Used to add `#include`s and other things that are required for the symbol to be declared. Since 1.0.0 an array is accepted too. When an array is passed, the items are concatenated together separated by a newline. System definitions should be passed via compiler args (eg: `_GNU_SOURCE` is often required for some symbols to be exposed on Linux, and it should be passed via `args` keyword argument).

 

compiler.find_library()

SYNOPSIS

dep compiler.find_library(

libname,
dirs:,
disabler: false,
has_headers:,
header_args:,
header_dependencies:,
header_include_directories:,
header_no_builtin_args: false,
header_prefix:,
required: true,
static: false,

)

DESCRIPTION

Tries to find the library specified in the positional argument.

POSARGS

libname str, required

The library to find.

KWARGS

dirs array[str]

Additional directories to search in.

By default the library is searched for in the system library directory (e.g. /usr/lib). Specifying more directories here, causes Meson to search in those directories as well as the system directories.

disabler bool, default: false, since 0.49.0

If `true`, this method will return a disabler on a failed check.

has_headers array[str], since 0.50.0

An array of headers that must be found as well. This check is equivalent to checking each header with a compiler.has_header call.

When used, kwargs that compiler.has_header would accept can be passed here prefixed with `header_`, and will have the same effect on the header check.

header_args array[str], since 0.51.0

When the `has_headers` kwarg is also used, this argument is passed to compiler.has_header as `args`.

header_dependencies dep | array[dep], since 0.51.0

When the `has_headers` kwarg is also used, this argument is passed to compiler.has_header as `dependencies`.

header_include_directories array[inc | str], since 0.51.0

When the `has_headers` kwarg is also used, this argument is passed to compiler.has_header as `include_directories`. (Since 1.10.0) Strings are also accepted.

header_no_builtin_args bool, default: false, since 0.51.0

When the `has_headers` kwarg is also used, this argument is passed to compiler.has_header as `no_builtin_args`.

header_prefix str, since 0.51.0

When the `has_headers` kwarg is also used, this argument is passed to compiler.has_header as `prefix`.

required bool | feature, default: true

If set `true`, Meson will abort with an error if the library could not be found. Otherwise, Meson will continue and the found method of the returned object will return `false`.

When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

(since 0.47.0) The value of a `feature` option can also be passed here.

static bool, default: false, since 0.51.0

If `true`, the search is limited to static libraries only. Setting this value to `false` (the default) will search for both shared and static libraries.

 

compiler.first_supported_argument()

SYNOPSIS

array[str] compiler.first_supported_argument(arg...)

since 0.43.0

DESCRIPTION

Given an array of strings, returns a singl-element array containing the first argument that passes the compiler.has_argument test or an empty array if none pass.

VARARGS

arg str, 0...N times

The arguments to check.

 

compiler.first_supported_link_argument()

SYNOPSIS

array[str] compiler.first_supported_link_argument(arg...)

since 0.46.0

DESCRIPTION

Given an array of strings, returns the first argument that passes the compiler.has_link_argument test or an empty array if none pass.

VARARGS

arg str, 0...N times

The link arguments to check.

 

compiler.get_argument_syntax()

SYNOPSIS

str compiler.get_argument_syntax()

since 0.49.0

DESCRIPTION

returns a string identifying the type of arguments the compiler takes. Can be one of `gcc`, `msvc`, or an undefined string value. This method is useful for identifying compilers that are not gcc or msvc, but use the same argument syntax as one of those two compilers such as clang or icc, especially when they use different syntax on different operating systems.

 

compiler.get_define()

SYNOPSIS

str compiler.get_define(

definename,
args:,
dependencies:,
include_directories:,
no_builtin_args: false,
prefix:,

)

since 0.40.0

DESCRIPTION

Returns the given preprocessor symbol's value as a string or empty string if it is not defined.

(since 0.47.0) This method will concatenate string literals as the compiler would. E.g. `"a" "b"` will become `"ab"`.

POSARGS

definename str, required

The define to check.

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

no_builtin_args bool, default: false

When set to `true`, the compiler arguments controlled by buil-in configuration options are not added.

prefix str | array[str]

Used to add `#include`s and other things that are required for the symbol to be declared. Since 1.0.0 an array is accepted too. When an array is passed, the items are concatenated together separated by a newline. System definitions should be passed via compiler args (eg: `_GNU_SOURCE` is often required for some symbols to be exposed on Linux, and it should be passed via `args` keyword argument).

 

compiler.get_id()

SYNOPSIS

str compiler.get_id()

DESCRIPTION

Returns a string identifying the compiler. For example, `gcc`, `msvc`, and more[36].

 

compiler.get_linker_id()

SYNOPSIS

str compiler.get_linker_id()

since 0.53.0

DESCRIPTION

Returns a string identifying the linker. For example, `ld.bfd`, `link`, and more[37].

 

compiler.get_supported_arguments()

SYNOPSIS

array[str] compiler.get_supported_arguments(

arg...,
checked: 'off',

)

since 0.43.0

DESCRIPTION

Returns an array containing only the arguments supported by the compiler, as if compiler.has_argument were called on them individually.

VARARGS

arg str, 0...N times

The arguments to check.

KWARGS

checked str, default: 'off', since 0.59.0

Supported values:
  - `'off'`: Quietly ignore unsupported arguments
  - `'warn'`: Print a warning for unsupported arguments
  - `'require'`: Abort if at least one argument is not supported

 

compiler.get_supported_function_attributes()

SYNOPSIS

array[str] compiler.get_supported_function_attributes()

since 0.48.0

DESCRIPTION

Returns an array containing any names that are supported GCC style attributes. Equivalent to compiler.has_function_attribute was called on each of them individually.

 

compiler.get_supported_link_arguments()

SYNOPSIS

array[str] compiler.get_supported_link_arguments(arg...)

since 0.46.0

DESCRIPTION

Returns an array containing only the arguments supported by the compiler, as if compiler.has_link_argument were called on them individually.

VARARGS

arg str, 0...N times

The link arguments to check.

 

compiler.has_argument()

SYNOPSIS

bool compiler.has_argument(argument, required: false)

DESCRIPTION

Returns `true` if the compiler accepts the specified command line argument, that is, can compile code without erroring out or printing a warning about an unknown flag.

POSARGS

argument str, required

The argument to check.

KWARGS

required bool | feature, default: false, since 1.3.0

When set to `true`, Meson will halt if the check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

 

compiler.has_define()

SYNOPSIS

bool compiler.has_define(

definename,
args:,
dependencies:,
include_directories:,
no_builtin_args: false,
prefix:,

)

since 1.3.0

DESCRIPTION

Returns true if the given preprocessor symbol is defined.

POSARGS

definename str, required

The define to check.

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

no_builtin_args bool, default: false

When set to `true`, the compiler arguments controlled by buil-in configuration options are not added.

prefix str | array[str]

Used to add `#include`s and other things that are required for the symbol to be declared. Since 1.0.0 an array is accepted too. When an array is passed, the items are concatenated together separated by a newline. System definitions should be passed via compiler args (eg: `_GNU_SOURCE` is often required for some symbols to be exposed on Linux, and it should be passed via `args` keyword argument).

 

compiler.has_function()

SYNOPSIS

bool compiler.has_function(

funcname,
args:,
dependencies:,
include_directories:,
no_builtin_args: false,
prefix:,
required: false,

)

DESCRIPTION

Returns true if the given function is provided by the standard library or a library passed in with the `args` keyword.

POSARGS

funcname str, required

The function to check.

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

no_builtin_args bool, default: false

When set to `true`, the compiler arguments controlled by buil-in configuration options are not added.

prefix str | array[str]

Used to add `#include`s and other things that are required for the symbol to be declared. Since 1.0.0 an array is accepted too. When an array is passed, the items are concatenated together separated by a newline. System definitions should be passed via compiler args (eg: `_GNU_SOURCE` is often required for some symbols to be exposed on Linux, and it should be passed via `args` keyword argument).

required bool | feature, default: false, since 1.3.0

When set to `true`, Meson will halt if the check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

 

compiler.has_function_attribute()

SYNOPSIS

bool compiler.has_function_attribute(

name,
required: false,

)

since 0.48.0

DESCRIPTION

Returns `true` if the compiler supports the GNU style (`__attribute__(...)`) `name`. This is preferable to manual compile checks as it may be optimized for compilers that do not support such attributes. This table[38] lists all of the supported attributes.

POSARGS

name str, required

The attribute name to check.

KWARGS

required bool | feature, default: false, since 1.3.0

When set to `true`, Meson will halt if the check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

 

compiler.has_header()

SYNOPSIS

bool compiler.has_header(

header_name,
args:,
dependencies:,
include_directories:,
no_builtin_args: false,
prefix:,
required: false,

)

DESCRIPTION

Returns true if the specified header is exists with the specified prefix, dependencies, and arguments.

This method is faster than compiler.check_header since it only does a pr-processor check.

POSARGS

header_name str, required

The header to check.

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

no_builtin_args bool, default: false

When set to `true`, the compiler arguments controlled by buil-in configuration options are not added.

prefix str | array[str]

Used to add `#include`s and other things that are required for the symbol to be declared. Since 1.0.0 an array is accepted too. When an array is passed, the items are concatenated together separated by a newline. System definitions should be passed via compiler args (eg: `_GNU_SOURCE` is often required for some symbols to be exposed on Linux, and it should be passed via `args` keyword argument).

required bool | feature, default: false, since 0.50.0

When set to `true`, Meson will halt if the header check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

 

compiler.has_header_symbol()

SYNOPSIS

bool compiler.has_header_symbol(

header,
symbol,
args:,
dependencies:,
include_directories:,
no_builtin_args: false,
prefix:,
required: false,

)

DESCRIPTION

Detects whether a particular symbol is declared in the specified header.

Symbols here include function, variable, `#define`, type definition, etc.

POSARGS

header str, required

The header to check.

symbol str, required

The symbol to check.

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

no_builtin_args bool, default: false

When set to `true`, the compiler arguments controlled by buil-in configuration options are not added.

prefix str | array[str]

Used to add `#include`s and other things that are required for the symbol to be declared. Since 1.0.0 an array is accepted too. When an array is passed, the items are concatenated together separated by a newline. System definitions should be passed via compiler args (eg: `_GNU_SOURCE` is often required for some symbols to be exposed on Linux, and it should be passed via `args` keyword argument).

required bool | feature, default: false, since 0.50.0

When set to `true`, Meson will halt if the header check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

 

compiler.has_link_argument()

SYNOPSIS

bool compiler.has_link_argument(argument, required: false)

since 0.46.0

DESCRIPTION

Returns `true` if the linker accepts the specified command line argument, that is, can compile and link code without erroring out or printing a warning about an unknown flag. Link arguments will be passed to the compiler, so should usually have the -Wl,` prefix. On VisualStudio a `/link` argument will be prepended.

POSARGS

argument str, required

The argument to check.

KWARGS

required bool | feature, default: false, since 1.3.0

When set to `true`, Meson will halt if the check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

 

compiler.has_member()

SYNOPSIS

bool compiler.has_member(

typename,
membername,
args:,
dependencies:,
include_directories:,
no_builtin_args: false,
prefix:,
required: false,

)

DESCRIPTION

Returns true if the type has the specified member.

POSARGS

typename str, required

The type to check.

membername str, required

The member to check.

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

no_builtin_args bool, default: false

When set to `true`, the compiler arguments controlled by buil-in configuration options are not added.

prefix str | array[str]

Used to add `#include`s and other things that are required for the symbol to be declared. Since 1.0.0 an array is accepted too. When an array is passed, the items are concatenated together separated by a newline. System definitions should be passed via compiler args (eg: `_GNU_SOURCE` is often required for some symbols to be exposed on Linux, and it should be passed via `args` keyword argument).

required bool | feature, default: false, since 1.3.0

When set to `true`, Meson will halt if the check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

 

compiler.has_members()

SYNOPSIS

bool compiler.has_members(

typename,
member...,
args:,
dependencies:,
include_directories:,
no_builtin_args: false,
prefix:,
required: false,

)

DESCRIPTION

Returns `true` if the type has all the specified members.

POSARGS

typename str, required

The type to check.

VARARGS

member str, 1...N times

The members to check

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

no_builtin_args bool, default: false

When set to `true`, the compiler arguments controlled by buil-in configuration options are not added.

prefix str | array[str]

Used to add `#include`s and other things that are required for the symbol to be declared. Since 1.0.0 an array is accepted too. When an array is passed, the items are concatenated together separated by a newline. System definitions should be passed via compiler args (eg: `_GNU_SOURCE` is often required for some symbols to be exposed on Linux, and it should be passed via `args` keyword argument).

required bool | feature, default: false, since 1.3.0

When set to `true`, Meson will halt if the check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

 

compiler.has_multi_arguments()

SYNOPSIS

bool compiler.has_multi_arguments(arg..., required: false)

since 0.37.0

DESCRIPTION

the same as compiler.has_argument but takes multiple arguments and uses them all in a single compiler invocation.

VARARGS

arg str, 0...N times

The arguments to check.

KWARGS

required bool | feature, default: false, since 1.3.0

When set to `true`, Meson will halt if the check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

 

compiler.has_multi_link_arguments()

SYNOPSIS

bool compiler.has_multi_link_arguments(

arg...,
required: false,

)

since 0.46.0

DESCRIPTION

the same as compiler.has_link_argument but takes multiple arguments and uses them all in a single compiler invocation.

VARARGS

arg str, 0...N times

The link arguments to check.

KWARGS

required bool | feature, default: false, since 1.3.0

When set to `true`, Meson will halt if the check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

 

compiler.has_type()

SYNOPSIS

bool compiler.has_type(

typename,
args:,
dependencies:,
include_directories:,
no_builtin_args: false,
prefix:,
required: false,

)

DESCRIPTION

Returns `true` if the specified token is a type.

POSARGS

typename str, required

The type to check.

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

no_builtin_args bool, default: false

When set to `true`, the compiler arguments controlled by buil-in configuration options are not added.

prefix str | array[str]

Used to add `#include`s and other things that are required for the symbol to be declared. Since 1.0.0 an array is accepted too. When an array is passed, the items are concatenated together separated by a newline. System definitions should be passed via compiler args (eg: `_GNU_SOURCE` is often required for some symbols to be exposed on Linux, and it should be passed via `args` keyword argument).

required bool | feature, default: false, since 1.3.0

When set to `true`, Meson will halt if the check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

 

compiler.links()

SYNOPSIS

bool compiler.links(

code,
args:,
dependencies:,
include_directories:,
name:,
no_builtin_args: false,
required: false,
werror: false,

)

DESCRIPTION

Returns true if the code compiles and links.

Since 0.60.0, if the `file` object's suffix does not match the compiler object's language, the compiler corresponding to the suffix is used to compile the source, while the target of the `links` method is used to link the resulting object file.

POSARGS

code str | file, required

The source code to check.

If a string is passed, the code is used directly. If a file object is passed, its content is used for the compiler check.

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

name str

The name to use for printing a message about the compiler check. If this keyword argument is not passed, no message will be printed about the check.

no_builtin_args bool, default: false

When set to `true`, the compiler arguments controlled by buil-in configuration options are not added.

required bool | feature, default: false, since 1.5.0

When set to `true`, Meson will halt if the check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

werror bool, default: false, since 1.3.0

When set to `true`, compiler warnings are treated as error.

 

compiler.preprocess()

SYNOPSIS

array[custom_idx] compiler.preprocess(

source...,
compile_args:,
dependencies:,
depends:,
include_directories:,
output:,

)

since 0.64.0

DESCRIPTION

Preprocess an array of source files but do not compile them. The preprocessor will receive the same arguments (include directories, defines, etc) as with normal compilation. That includes for example args added with `add_project_arguments()`, or on the command line with -Dc_args-DFOO`.

VARARGS

source str | file | custom_tgt | custom_idx | generated_list, 0...N times

Input source to preprocess. The following types are supported:

- Strings relative to the current source directory
- file objects defined in any preceding build file
- The return value of configur-time generators such as configure_file
- The return value of buil-time generators such as custom_target or generator.process

KWARGS

compile_args array[str]

Extra flags to pass to the preprocessor

dependencies dep | array[dep], since 1.1.0

Additionally dependencies required.

depends array[build_tgt | custom_tgt], since 1.4.0

Specifies that this target depends on the specified target(s). These targets should be built before starting to preprocess an input.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

output str

Template for name of preprocessed files: `@PLAINNAME@` is replaced by the source filename and `@BASENAME@` is replaced by the source filename without its extension.

 

compiler.run()

SYNOPSIS

runresult compiler.run(

code,
args:,
dependencies:,
include_directories:,
name:,
no_builtin_args: false,
required: false,
werror: false,

)

DESCRIPTION

Attempts to compile and execute the given code fragment.

POSARGS

code str | file, required

The source code to check.

If a string is passed, the code is used directly. If a file object is passed, its content is used for the compiler check.

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

name str

The name to use for printing a message about the compiler check. If this keyword argument is not passed, no message will be printed about the check.

no_builtin_args bool, default: false

When set to `true`, the compiler arguments controlled by buil-in configuration options are not added.

required bool | feature, default: false, since 1.5.0

When set to `true`, Meson will halt if the check fails. When set to a `feature`[0] option, the feature will control if it is searched and whether to fail if not found.

werror bool, default: false, since 1.3.0

When set to `true`, compiler warnings are treated as error.

 

compiler.sizeof()

SYNOPSIS

int compiler.sizeof(

typename,
args:,
dependencies:,
include_directories:,
no_builtin_args: false,
prefix:,

)

DESCRIPTION

returns the size of the given type (e.g. `'int'`) or-1 if the type is unknown. For -like languages, the header `stddef.h` and `stdio.h` are included implicitly for native compilation, only `stddef.h` is included when cros-compiling.

POSARGS

typename str, required

The type to compute.

KWARGS

args array[str]

Used to pass an array of compiler arguments. Defining include paths for headers not in the default include path via -Isome/path/to/header` is generally supported, however, usually not recommended.

This is because include directories can also be specified via the `include_directories` or the `dependency` kwarg (if present). The same is also true for passing libraries to link with -lfoo`.

dependencies dep | array[dep]

Additionally dependencies required for compiling and / or linking.

include_directories array[inc | str], since 0.38.0

Extra directories for header searches, created with the include_directories function. (Since 1.10.0) Strings are also accepted.

no_builtin_args bool, default: false

When set to `true`, the compiler arguments controlled by buil-in configuration options are not added.

prefix str | array[str]

Used to add `#include`s and other things that are required for the symbol to be declared. Since 1.0.0 an array is accepted too. When an array is passed, the items are concatenated together separated by a newline. System definitions should be passed via compiler args (eg: `_GNU_SOURCE` is often required for some symbols to be exposed on Linux, and it should be passed via `args` keyword argument).

 

compiler.symbols_have_underscore_prefix()

SYNOPSIS

bool compiler.symbols_have_underscore_prefix()

since 0.37.0

DESCRIPTION

Returns `true` if the C symbol mangling is one underscore (`_`) prefixed to the symbol.

 

compiler.version()

SYNOPSIS

str compiler.version()

DESCRIPTION

Returns the compiler's version number as a string.

 

custom_idx.full_path()

SYNOPSIS

str custom_idx.full_path()

since 0.54.0

DESCRIPTION

Returns a full path pointing to the result target file NOTE: In most cases using the object itself will do the same job as this and will also allow Meson to setup inte-target dependencies correctly. Please file a bug if that doesn't work for you.

See custom_tgt.full_path

 

custom_tgt.[index]()

SYNOPSIS

custom_idx custom_tgt.[index]()

DESCRIPTION

Returns an opaque object that references this target, and can be used as a source in other targets. When it is used as such it will make that target depend on this custom target, but the only source added will be the one that corresponds to the index of the custom target's output argument.

 

custom_tgt.full_path()

SYNOPSIS

str custom_tgt.full_path()

DESCRIPTION

Returns a full path pointing to the result target file NOTE: In most cases using the object itself will do the same job as this and will also allow Meson to setup inte-target dependencies correctly. Please file a bug if that doesn't work for you. (since 0.54.0) It can be also called on indexes objects: `custom_targets[i].full_path()`.

 

custom_tgt.to_list()

SYNOPSIS

array[custom_idx] custom_tgt.to_list()

since 0.54.0

DESCRIPTION

Returns an array of opaque objects that references this target, and can be used as a source in other targets. This can be used to iterate outputs with `foreach` loop.

 

dep.as_link_whole()

SYNOPSIS

dep dep.as_link_whole()

since 0.56.0

DESCRIPTION

Only dependencies created with declare_dependency, returns a copy of the dependency object with all link_with arguments changed to link_whole. This is useful for example for fallback dependency from a subproject built with `default_library=static`. Note that all `link_with` objects must be static libraries otherwise an error will be raised when trying to `link_whole` a shared library.

 

dep.as_shared()

SYNOPSIS

dep dep.as_shared(recursive:)

since 1.6.0

DESCRIPTION

Only for dependencies created with declare_dependency, returns a copy of the dependency object that prefer the `shared` version of both_libraries.

KWARGS

recursive bool

If true, this is recursively applied to dependencies

 

dep.as_static()

SYNOPSIS

dep dep.as_static(recursive:)

since 1.6.0

DESCRIPTION

Only for dependencies created with declare_dependency, returns a copy of the dependency object that prefer the `static` version of both_libraries.

KWARGS

recursive bool

If true, this is recursively applied to dependencies

 

dep.as_system()

SYNOPSIS

dep dep.as_system([value])

since 0.52.0

DESCRIPTION

Returns a copy of the dependency object, which has changed the value of `include_type` to `value`. The `value` argument is optional and defaults to `'preserve'`.

OPTARGS

value str

The new value. See dependency for supported values.

 

dep.found()

SYNOPSIS

bool dep.found()

DESCRIPTION

Returns whether the dependency was found.

 

dep.get_configtool_variable()

SYNOPSIS

str dep.get_configtool_variable(var_name)

deprecated since 0.56.0, since 0.44.0

DESCRIPTION

Gets the command line argument from the config tool (with -` prepended), or, if invoked on a non confi-tool dependency, error out.

POSARGS

var_name str, required

Name of the variable to query

 

dep.get_pkgconfig_variable()

SYNOPSIS

str dep.get_pkgconfig_variable(

var_name,
default:,
define_variable:,

)

deprecated since 0.56.0, since 0.36.0

DESCRIPTION

Gets the pk-config variable specified, or, if invoked on a non pk-config dependency, error out.

POSARGS

var_name str, required

Name of the variable to query

KWARGS

default str, since 0.45.0

The value to return if the variable was not found. A warning is issued if the variable is not defined and this kwarg is not set.

define_variable array[str], since 0.44.0

You can also redefine a variable by passing an array to this kwarg that can affect the retrieved variable: `['prefix', '/'])`.

(Since 1.3.0) Multiple variables can be specified in pairs.

 

dep.get_variable()

SYNOPSIS

str dep.get_variable(

[varname],
cmake:,
configtool:,
default_value:,
internal:,
pkgconfig:,
pkgconfig_define:,
system:,

)

since 0.51.0

DESCRIPTION

A generic variable getter method, which replaces the `get_type_variable` methods. This allows one to get the variable from a dependency without knowing specifically how that dependency was found. If `default_value` is set and the value cannot be gotten from the object then `default_value` is returned, if it is not set then an error is raised.

OPTARGS

varname str, since 0.58.0

This argument is used as a default value for `cmake`, `pkgconfig`, `configtool`, `internal` and `system` keyword arguments. It is useful in the common case where `pkgconfig` and `internal` use the same variable name, in which case it's easier to write `dep.get_variable('foo')` instead of `dep.get_variable(pkgconfig: 'foo', internal: 'foo')`.

KWARGS

cmake str

The CMake variable name

configtool str

The configtool variable name

default_value str

The default value to return when the variable does not exist

internal str, since 0.54.0

The internal variable name

pkgconfig str

The pkgconfig variable name

pkgconfig_define array[str]

See dep.get_pkgconfig_variable

system str, since 1.6.0

The system variable name

WARNINGS

Before 1.3.0, specifying multiple pkgconfig_define pairs would silently malform the results. Only the first variable would be redefined, but its value would contain both the second variable name, as well as its value.

 

dep.include_type()

SYNOPSIS

str dep.include_type()

since 0.52.0

DESCRIPTION

Returns the value set by the `include_type` kwarg.

 

dep.name()

SYNOPSIS

str dep.name()

since 0.48.0

DESCRIPTION

Returns the name of the dependency that was searched. Returns `'internal'` for dependencies created with declare_dependency.

NOTE: This was not implemented for dep objects returned by compiler.find_library until Meson 1.5.0

 

dep.partial_dependency()

SYNOPSIS

dep dep.partial_dependency(

compile_args: false,
includes: false,
link_args: false,
links: false,
sources: false,

)

since 0.46.0

DESCRIPTION

Returns a new dependency object with the same name, version, found status, type name, and methods as the object that called it. This new object will only inherit other attributes from its parent as controlled by keyword arguments.

If the parent has any dependencies, those will be applied to the new partial dependency with the same rules. So, given:

dep1 = declare_dependency(compile_args : -Werror=foo', link_with : 'libfoo')
dep2 = declare_dependency(compile_args : -Werror=bar', dependencies : dep1)
dep3 = dep2.partial_dependency(compile_args : true)

dep3 will add `[-Werror=foo', -Werror=bar']` to the compiler args of any target it is added to, but libfoo will not be added to the link_args.

The following arguments will add the following attributes:

- compile_args: any arguments passed to the compiler
- link_args: any arguments passed to the linker
- links: anything passed via link_with or link_whole
- includes: any include_directories
- sources: any compiled or static sources the dependency has

KWARGS

compile_args bool, default: false

Whether to include compile_args

includes bool, default: false

Whether to include includes

link_args bool, default: false

Whether to include link_args

links bool, default: false

Whether to include links

sources bool, default: false

Whether to include sources

WARNINGS

A bug present until 0.50.1 results in the above behavior not working correctly.

 

dep.type_name()

SYNOPSIS

str dep.type_name()

DESCRIPTION

Returns a string describing the type of the dependency, the most common values are `internal` for deps created with declare_dependency and `pkgconfig` for system dependencies obtained with Pk-config.

 

dep.version()

SYNOPSIS

str dep.version()

DESCRIPTION

the version number as a string, for example `1.2.8`. `unknown` if the dependency provider doesn't support determining the version.

 

dict.get()

SYNOPSIS

any dict.get(key, [fallback])

DESCRIPTION

returns the value for the key given as first argument if it is present in the dictionary, or the optional fallback value given as the second argument. If a single argument was given and the key was not found, causes a fatal error

POSARGS

key str, required

The key to query.

OPTARGS

fallback any

Fallback value that is returned if the key is not in the dict.

 

dict.has_key()

SYNOPSIS

bool dict.has_key(key)

DESCRIPTION

Returns `true` if the dictionary contains the key given as argument, `false` otherwise.

POSARGS

key str, required

The key to query.

 

dict.keys()

SYNOPSIS

array[str] dict.keys()

DESCRIPTION

Returns an array of keys in the dictionary, sorted in ascending order.

 

dict.values()

SYNOPSIS

array[any] dict.values()

since 1.10.0

DESCRIPTION

Returns an array of values in the dictionary, sorted by the corresponding keys in ascending order.

 

disabler.found()

SYNOPSIS

bool disabler.found()

DESCRIPTION

Always returns `false`

 

env.append()

SYNOPSIS

void env.append(variable, Value..., separator:)

DESCRIPTION

appends the given values to the old value of the environment variable, e.g. `env.append('FOO', 'BAR', 'BAZ', separator : ';')` produces `BOB;BAR;BAZ` if `FOO` had the value `BOB` and plain `BAR;BAZ` if the value was not defined.

POSARGS

variable str, required

The variable to modify

VARARGS

Value str, 0...N times

The values to append

KWARGS

separator str

The separator to use. If not explicitly specified, the default path separator for the host operating system will be used, i.e. ';' for Windows and ':' for UNIX/POSIX systems.

 

env.prepend()

SYNOPSIS

void env.prepend(variable, Value..., separator:)

DESCRIPTION

Same as `append` except that it writes to the beginning of the variable.

POSARGS

variable str, required

The variable to modify

VARARGS

Value str, 0...N times

The values to prepend

KWARGS

separator str

The separator to use. If not explicitly specified, the default path separator for the host operating system will be used, i.e. ';' for Windows and ':' for UNIX/POSIX systems.

 

env.set()

SYNOPSIS

void env.set(variable, Value..., separator:)

DESCRIPTION

Sets the environment variable specified in the first argument to the values in the varargs joined by the separator. For instance, `env.set('FOO', 'BAR'),` sets envvar `FOO` to value `BAR`.

POSARGS

variable str, required

The variable to modify

VARARGS

Value str, 0...N times

The values to set

KWARGS

separator str

The separator to use. If not explicitly specified, the default path separator for the host operating system will be used, i.e. ';' for Windows and ':' for UNIX/POSIX systems.

 

env.unset()

SYNOPSIS

void env.unset()

since 1.4.0

DESCRIPTION

Unset the specified environment variable. If this variable does not exist, nothing happens.

 

external_program.cmd_array()

SYNOPSIS

array[str] external_program.cmd_array()

since 1.10.0

DESCRIPTION

Returns an array containing the command(s) for the program.

 

external_program.found()

SYNOPSIS

bool external_program.found()

DESCRIPTION

Returns whether the executable was found.

 

external_program.full_path()

SYNOPSIS

str external_program.full_path()

since 0.55.0

DESCRIPTION

Returns a string pointing to the script or executable.

NOTE: You should not usually need to use this method. Passing the object itself should work in most contexts where a program can appear, and allows Meson to setup inte-target dependencies correctly (for example in cases where a program might be overridden by a build_tgt). Only use this if you specifically need a string, such as when embedding a program path into a header file, or storing it into an environment variable.

For example:

run_command(find_program('foo'), 'arg1', 'arg2')

 

external_program.path()

SYNOPSIS

str external_program.path()

deprecated since 0.55.0

DESCRIPTION

Deprecated: Use external_program.full_path instead.

Returns a string pointing to the script or executable.

NOTE: You should not usually need to use this method. Passing the object itself should work in most contexts where a program can appear, and allows Meson to setup inte-target dependencies correctly (for example in cases where a program might be overridden by a build_tgt). Only use this if you specifically need a string, such as when embedding a program path into a header file, or storing it into an environment variable.

For example:

run_command(find_program('foo'), 'arg1', 'arg2')

 

external_program.version()

SYNOPSIS

str external_program.version()

since 0.62.0

DESCRIPTION

The version number as a string, for example `1.2.8`.

`unknown` if the program cannot determine the version via a -version` argument.

 

feature.allowed()

SYNOPSIS

bool feature.allowed()

since 0.59.0

DESCRIPTION

Returns whether the feature was set to `'enabled'` or `'auto'`

 

feature.auto()

SYNOPSIS

bool feature.auto()

DESCRIPTION

Returns whether the feature was set to `'auto'`

 

feature.disable_auto_if()

SYNOPSIS

feature feature.disable_auto_if(value)

since 0.59.0

DESCRIPTION

Returns the feature, with `'auto'` converted to `'disabled'` if value is true.

| Feature | `value = true` | `value = false` | |- |- |- | | Auto | Disabled | Auto | | Enabled | Enabled | Enabled | | Disabled | Disabled | Disabled |

POSARGS

value bool, required

See the table above

EXAMPLE

`disable_auto_if` is useful to give precedence to mutually exclusive dependencies (that provide the same API) if either or both are available:

# -Dfoo=auto-Dbar=enabled' will not pick foo even if installed.
use_bar = get_option('bar')
use_foo = get_option('foo').disable_auto_if(use_bar.enabled())
dep_foo = dependency('foo', required: use_foo)
if not dep_foo.found()

  dep_foo = dependency('bar', required: use_bar)
endif

 

feature.disable_if()

SYNOPSIS

feature feature.disable_if(value, error_message: '')

since 1.1.0

DESCRIPTION

Returns the object itself if the value is false; an error if the object is `'enabled'` and the value is true; a disabled feature if the object is `'auto'` or `'disabled'` and the value is true.

| Feature | `value = true` | `value = false` | |- |- |- | | Auto | Disabled | Auto | | Enabled | Error | Enabled | | Disabled | Disabled | Disabled |

This is equivalent to `feature_opt.require(not condition)`, but may make code easier to reason about, especially when mixed with `enable_if`

POSARGS

value bool, required

The value to check

KWARGS

error_message str, default: ''

The error message to print if the check fails

EXAMPLE

`disable_if` is useful to restrict the applicability of `'auto'` features, particularly when passing them to dependency:

use_os_feature = get_option('foo')

  .disable_if(host_machine.system() == 'darwin', error_message : 'os feature not supported on MacOS')
dep_os_feature = dependency('os_feature', required: use_os_feature)

 

feature.disabled()

SYNOPSIS

bool feature.disabled()

DESCRIPTION

Returns whether the feature was set to `'disabled'`

 

feature.enable_auto_if()

SYNOPSIS

feature feature.enable_auto_if(value)

since 1.1.0

DESCRIPTION

Returns the feature, with `'auto'` converted to `'enabled'` if value is true.

| Feature | `value = true` | `value = false` | |- |- |- | | Auto | Enabled | Auto | | Enabled | Enabled | Enabled | | Disabled | Disabled | Disabled |

POSARGS

value bool, required

See the table above

 

feature.enable_if()

SYNOPSIS

feature feature.enable_if(value, error_message: '')

since 1.1.0

DESCRIPTION

Returns the object itself if the value is false; an error if the object is `'disabled'` and the value is true; an enabled feature if the object is `'auto'` or `'enabled'` and the value is true.

| Feature | `value = true` | `value = false` | |- |- |- | | Auto | Enabled | Auto | | Enabled | Enabled | Enabled | | Disabled | Error | Disabled |

POSARGS

value bool, required

The value to check

KWARGS

error_message str, default: ''

The error message to print if the check fails

EXAMPLE

`enable_if` is useful to restrict the applicability of `'auto'` features, particularly when passing them to dependency:

use_llvm = get_option('llvm').enable_if(with_clang).enable_if(with_llvm_libs)
dep_llvm = dependency('llvm', required: use_llvm)

 

feature.enabled()

SYNOPSIS

bool feature.enabled()

DESCRIPTION

Returns whether the feature was set to `'enabled'`

 

feature.require()

SYNOPSIS

feature feature.require(value, error_message: '')

since 0.59.0

DESCRIPTION

Returns the object itself if the value is true; an error if the object is `'enabled'` and the value is false; a disabled feature if the object is `'auto'` or `'disabled'` and the value is false.

| Feature | `value = true` | `value = false` | |- |- |- | | Auto | Auto | Disabled | | Enabled | Enabled | Error | | Disabled | Disabled | Disabled |

POSARGS

value bool, required

The value to check

KWARGS

error_message str, default: ''

The error message to print if the check fails

EXAMPLE

`require` is useful to restrict the applicability of `'auto'` features, for example based on other features or on properties of the host machine:

if get_option('directx').require(host_machine.system() == 'windows',

      error_message: 'DirectX only available on Windows').allowed()

  src += ['directx.c']

  config.set10('HAVE_DIRECTX', true)
endif

 

file.full_path()

SYNOPSIS

str file.full_path()

since 1.4.0

DESCRIPTION

Returns a full path pointing to the file. This is useful for printing the path with e.g message function for debugging purpose. NOTE: In most cases using the object itself will do the same job as this and will also allow Meson to setup dependencies correctly.

 

generator.process()

SYNOPSIS

generated_list generator.process(

source...,
env:,
extra_args:,
preserve_path_from:,

)

DESCRIPTION

Takes an array of files, causes them to be processed and returns an object containing the result which can then, for example, be passed into a build target definition.

VARARGS

source str | file | custom_tgt | custom_idx | generated_list, 1...N times

sources to process.

KWARGS

env env | array[str] | dict[str], since 1.3.0

environment variables to set, such as `{'NAME1': 'value1', 'NAME2': 'value2'}` or `['NAME1=value1', 'NAME2=value2']`, or an env object which allows more sophisticated environment juggling.

extra_args array[str]

If present, will be used to replace an entry `@EXTRA_ARGS@` in the argument array.

preserve_path_from str, since 0.45.0

If given, specifies that the output files need to maintain their directory structure inside the target temporary directory. The most common value for this is `meson.current_source_dir()`. With this value when a file called `subdir/one.input` is processed it generates a file `{target private directory}/subdir/one.out` as opposed to `{target private directory}/one.out`.

 

int.is_even()

SYNOPSIS

bool int.is_even()

DESCRIPTION

Returns true if the number is even.

 

int.is_odd()

SYNOPSIS

bool int.is_odd()

DESCRIPTION

Returns true if the number is odd

 

int.to_string()

SYNOPSIS

str int.to_string([fill])

DESCRIPTION

Returns the value of the number as a string.

OPTARGS

fill int

Left fill the string with zeros until it reaches the length specified by this argument. A leading negative sign counts towards the length, and is handled by inserting the padding after the -` character rather than before. The original string is returned if the value provided is less than or equal to the former's length.

 

meson.add_devenv()

SYNOPSIS

void meson.add_devenv(env, method:, separator:)

since 0.58.0

DESCRIPTION

add an env object (returned by environment) to the list of environments that will be applied when using `meson devenv`[39] command line.

This is useful for developers who wish to use the project without installing it, it is often needed to set for example the path to plugins directory, etc. Alternatively, a list or dictionary can be passed as first argument.

devenv = environment()
devenv.set('PLUGINS_PATH', meson.current_build_dir())
...
meson.add_devenv(devenv)

After configuring and compiling that project, a terminal can be opened with the environment set:

sh
$ meson devenv-C <builddir>
$ echo $PLUGINS_PATH
/path/to/source/subdir

See `meson devenv`[38] command documentation for a list of environment variables that are set by default by Meson.

POSARGS

env env | str | array[str] | dict[str] | dict[array[str]], required

The env object to add. Since 0.62.0 array of strings is allowed in dictionary values. In that case values are joined using the separator.

KWARGS

method str, since 0.62.0

Must be one of 'set', 'prepend', or 'append' (defaults to 'set'). Controls if initial values defined in the first positional argument are prepended, appended or replace the current value of the environment variable.

separator str, since 0.62.0

The separator to use for the initial values defined in the first positional argument. If not explicitly specified, the default path separator for the host operating system will be used, i.e. ';' for Windows and ':' for UNIX/POSIX systems.

 

meson.add_dist_script()

SYNOPSIS

void meson.add_dist_script(script_name, arg...)

since 0.48.0

DESCRIPTION

Causes the script given as argument to run during `dist` operation after the distribution source has been generated but before it is archived. Note that this runs the script file that is in the _staging_ directory, not the one in the source directory. If the script file cannot be found in the staging directory, it is a hard error. The `MESON_DIST_ROOT` environment variables is set when dist scripts is run.

(since 0.54.0) The `MESON_SOURCE_ROOT` and `MESON_BUILD_ROOT` environment variables are set when dist scripts are run. They are path to the root source and build directory of the main project, even when the script comes from a subproject.

(since 0.58.0) This command can be invoked from a subproject, it was a hard error in earlier versions. Subproject dist scripts will only be executed when running `meson dist-includ-subprojects`. `MESON_PROJECT_SOURCE_ROOT`, `MESON_PROJECT_BUILD_ROOT` and `MESON_PROJECT_DIST_ROOT` environment variables are set when dist scripts are run. They are identical to `MESON_SOURCE_ROOT`, `MESON_BUILD_ROOT` and `MESON_DIST_ROOT` for main project scripts, but for subproject scripts they have the path to the root of the subproject appended, usually `subprojects/<subprojec-name>`.

(since 1.4.0) The `MESONREWRITE` environment variable contains the path to the rewrite command that corresponds to the `meson` executable that was used to configure the build. (This might be a different path than the first executable found in `PATH`.) It can be used to remove or replace any run_command that depends on the revision control system from the build configuration. Note that the value will contain many parts. For example, it may be `python3 /path/to/meson.py introspect`. The user is responsible for splitting the string to an array if needed by splitting lexically like a UNIX shell would. If your script uses Python, `shlex.split()` is the easiest correct way to do this.

POSARGS

script_name str | file | external_program, required

The script to execute.

(since 0.55.0) The output of find_program as well as strings are accepted.

(since 0.57.0) file objects and the output of configure_file may be used.

VARARGS

arg str | file | external_program, 0...N times, since 0.49.0

Additional arguments

(since 0.55.0) The output of configure_file, files, and find_program as well as strings are accepted.

 

meson.add_install_script()

SYNOPSIS

void meson.add_install_script(

script_name,
arg...,
dry_run: false,
install_tag:,
skip_if_destdir: false,

)

DESCRIPTION

Causes the script given as an argument to be run during the install step, this script will have the environment variables `MESON_SOURCE_ROOT`, `MESON_BUILD_ROOT`, `MESON_INSTALL_PREFIX`, `MESON_INSTALL_DESTDIR_PREFIX`, and `MESONINTROSPECT` set. All positional arguments are passed as parameters.

(since 0.54.0) If `meson install` is called with the -quiet` option, the environment variable `MESON_INSTALL_QUIET` will be set.

(since 1.1.0) If `meson install` is called with the -dr-run` option, the environment variable `MESON_INSTALL_DRY_RUN` will be set.

Meson uses the `DESTDIR` environment variable as set by the inherited environment to determine the (temporary) installation location for files. Your install script must be aware of this while manipulating and installing files. The correct way to handle this is with the `MESON_INSTALL_DESTDIR_PREFIX` variable which is always set and contains `DESTDIR` (if set) and `prefix` joined together. This is useful because both are usually absolute paths and there are platfor-specific edg-cases in joining two absolute paths.

In case it is needed, `MESON_INSTALL_PREFIX` is also always set and has the value of the `prefix` option passed to Meson.

`MESONINTROSPECT` contains the path to the introspect command that corresponds to the `meson` executable that was used to configure the build. (This might be a different path than the first executable found in `PATH`.) It can be used to query build configuration. Note that the value will contain many parts, f.ex., it may be `python3 /path/to/meson.py introspect`. The user is responsible for splitting the string to an array if needed by splitting lexically like a UNIX shell would. If your script uses Python, `shlex.split()` is the easiest correct way to do this.

POSARGS

script_name str | file | external_program | exe | custom_tgt | custom_idx, required

The script to execute.

(since 0.55.0) The output of find_program, executable, custom_target, as well as strings are accepted.

(since 0.57.0) file objects and the output of configure_file may be used.

VARARGS

arg str | file | external_program | exe | custom_tgt | custom_idx, 0...N times, since 0.49.0

Additional arguments

(since 0.55.0) The output of find_program, executable, custom_target, as well as strings are accepted.

KWARGS

dry_run bool, default: false, since 1.1.0

If `true` the script will be run even if -dr-run` option is provided to the `meson install` command. The script can use the `MESON_INSTALL_DRY_RUN` variable to determine if it is in dry run mode or not.

install_tag str, since 0.60.0

A string used by the `meson install-tags` command to install only a subset of the files. By default the script has no install tag which means it is not being run when `meson install-tags` argument is specified.

skip_if_destdir bool, default: false, since 0.57.0

If `true` the script will not be run if DESTDIR is set during installation. This is useful in the case the script updates system wide cache that is only needed when copying files into final destination.

 

meson.add_postconf_script()

SYNOPSIS

void meson.add_postconf_script(script_name, arg...)

DESCRIPTION

Runs the given command after all project files have been generated. This script will have the environment variables `MESON_SOURCE_ROOT` and `MESON_BUILD_ROOT` set.

POSARGS

script_name str | file | external_program, required

The script to execute.

(since 0.55.0) The output of find_program as well as strings are accepted.

(since 0.57.0) file objects and the output of configure_file may be used.

VARARGS

arg str | file | external_program, 0...N times, since 0.49.0

Additional arguments

(since 0.55.0) The output of configure_file, files, and find_program as well as strings are accepted.

 

meson.backend()

SYNOPSIS

str meson.backend()

since 0.37.0

DESCRIPTION

Returns a string representing the current backend:

- `ninja`
- `vs2010`
- `vs2012`
- `vs2013`
- `vs2015`
- `vs2017`
- `vs2019`
- `vs2022`
- `xcode`

 

meson.build_options()

SYNOPSIS

str meson.build_options()

since 1.1.0

DESCRIPTION

Returns a string with the configuration line used to set the current project up.

NOTES

Do not try to parse this string!

You should use cfg_data.set_quoted to safely escape any embedded quotes prior to storing it into e.g. a C header macro.

The contents returned by this function are the same as the "Build Options:" line reported in `<builddir>/meso-logs/meso-log.txt`.

 

meson.build_root()

SYNOPSIS

str meson.build_root()

deprecated since 0.56.0

DESCRIPTION

Returns a string with the absolute path to the build root directory. This function will return the build root of the parent project if called from a subproject, which is usually not what you want. Try using meson.current_build_dir or meson.project_build_root. In the rare cases where the root of the main project is needed, use meson.global_build_root that has the same behaviour but with a more explicit name.

 

meson.can_run_host_binaries()

SYNOPSIS

bool meson.can_run_host_binaries()

since 0.55.0

DESCRIPTION

Returns true if the build machine can run binaries compiled for the host. This returns `true` unless you are cross compiling, need a helper to run host binaries, and don't have one. For example when cross compiling from Linux to Windows, one can use `wine` as the helper.

 

meson.current_build_dir()

SYNOPSIS

str meson.current_build_dir()

DESCRIPTION

Returns a string with the absolute path to the current build directory.

 

meson.current_source_dir()

SYNOPSIS

str meson.current_source_dir()

DESCRIPTION

Returns a string to the current source directory.

NOTES

You do not need to use this function!

When passing files from the current source directory to a function since that is the default. Also, you can use the files function to refer to files in the current or any other source directory instead of constructing paths manually with meson.current_source_dir.

 

meson.get_compiler()

SYNOPSIS

compiler meson.get_compiler(language, native: false)

DESCRIPTION

Returns a compiler object describing a compiler.

POSARGS

language str, required

The language of the compiler to return.

See our list of supported languages[40].

KWARGS

native bool, default: false

When set to `true` Meson returns the compiler for the build machine (the "native" compiler) and when `false` it returns the host compiler (the "cross" compiler). If `native` is omitted, Meson returns the "cross" compiler if we're currently cros-compiling and the "native" compiler if we're not.

 

meson.get_cross_property()

SYNOPSIS

any meson.get_cross_property(propname, [fallback_value])

deprecated since 0.58.0

DESCRIPTION

Returns the given property from a cross file, the optional fallback_value is returned if not cross compiling or the given property is not found.

This method is replaced by meson.get_external_property.

POSARGS

propname str, required

Name of the property in the cross / native file.

OPTARGS

fallback_value any

Value to return if `propname` is not set in the machine file.

 

meson.get_external_property()

SYNOPSIS

any meson.get_external_property(

propname,
[fallback_value],
native:,

)

since 0.54.0

DESCRIPTION

Returns the given property from a native or cross file. The optional fallback_value is returned if the given property is not found.

POSARGS

propname str, required

Name of the property in the cross / native file.

OPTARGS

fallback_value any

Value to return if `propname` is not set in the machine file.

KWARGS

native bool

Setting `native` to `true` forces retrieving a variable from the native file, even when cros-compiling. If `native: false` or not specified, the variable is retrieved from the cros-file if cros-compiling, and from the nativ-file when not cros-compiling.

 

meson.global_build_root()

SYNOPSIS

str meson.global_build_root()

since 0.58.0

DESCRIPTION

Returns a string with the absolute path to the build root directory. This function will return the build root of the main project if called from a subproject, which is usually not what you want. It is usually preferable to use meson.current_build_dir or meson.project_build_root.

 

meson.global_source_root()

SYNOPSIS

str meson.global_source_root()

since 0.58.0

DESCRIPTION

Returns a string with the absolute path to the source root directory. This function will return the source root of the main project if called from a subproject, which is usually not what you want. It is usually preferable to use meson.current_source_dir or meson.project_source_root.

 

meson.has_exe_wrapper()

SYNOPSIS

bool meson.has_exe_wrapper()

deprecated since 0.55.0

DESCRIPTION

Use meson.can_run_host_binaries instead.

 

meson.has_external_property()

SYNOPSIS

bool meson.has_external_property(propname, native:)

since 0.58.0

DESCRIPTION

Checks whether the given property exist in a native or cross file.

POSARGS

propname str, required

Name of the property in the cross / native file.

KWARGS

native bool

Setting `native` to `true` forces retrieving a variable from the native file, even when cros-compiling. If `native: false` or not specified, the variable is retrieved from the cros-file if cros-compiling, and from the nativ-file when not cros-compiling.

 

meson.install_dependency_manifest()

SYNOPSIS

void meson.install_dependency_manifest(output_name)

DESCRIPTION

Installs a manifest file containing a list of all subprojects, their versions and license names to the file name given as the argument.

If license files are defined as well, they will be copied next to the manifest and referenced in it.

If this function is not used, the builtin option `licensedir` can be used to install the manifest to a given directory with the name `depmf.json`.

POSARGS

output_name str, required

Name of the manifest file to install

 

meson.is_cross_build()

SYNOPSIS

bool meson.is_cross_build()

DESCRIPTION

Returns `true` if the current build is a cross build[41] and `false` otherwise.

 

meson.is_subproject()

SYNOPSIS

bool meson.is_subproject()

DESCRIPTION

Returns `true` if the current project is being built as a subproject of some other project and `false` otherwise.

 

meson.is_unity()

SYNOPSIS

bool meson.is_unity()

DESCRIPTION

Returns `true` when doing a unity build[42] (multiple sources are combined before compilation to reduce build time) and `false` otherwise.

 

meson.override_dependency()

SYNOPSIS

void meson.override_dependency(

name,
dep_object,
native: false,
static:,

)

since 0.54.0

DESCRIPTION

Specifies that whenever dependency with `name` is used, Meson should not look it up on the system but instead return `dep_object`, which may either be the result of dependency or declare_dependency.

Doing this in a subproject allows the parent project to retrieve the dependency without having to know the dependency variable name: `dependency(name, fallback : subproject_name)`.

POSARGS

name str, required

The name of the dependency to override.

dep_object dep, required

The dependency to set as the override for `name`.

KWARGS

native bool, default: false

If set to `true`, the dependency is always overwritten for the build machine. Otherwise, the dependency is overwritten for the host machine, which differs from the build machine when cros-compiling.

static bool, since 0.60.0

Used to override static and/or shared dependencies separately. If not specified it is assumed `dep_object` follows `default_library` option value.

 

meson.override_find_program()

SYNOPSIS

void meson.override_find_program(progname, program)

since 0.46.0

DESCRIPTION

specifies that whenever find_program is used to find a program named `progname`, Meson should not look it up on the system but instead return `program`, which may either be the result of find_program, configure_file or executable.

(since 0.55.0) If a version check is passed to find_program for a program that has been overridden with an executable, the current project version is used.

POSARGS

progname str, required

The name of the program to override.

program exe | file | external_program, required

The program to set as the override for `progname`.

 

meson.project_build_root()

SYNOPSIS

str meson.project_build_root()

since 0.56.0

DESCRIPTION

Returns a string with the absolute path to the build root directory of the current (sub)project.

 

meson.project_license()

SYNOPSIS

array[str] meson.project_license()

since 0.45.0

DESCRIPTION

Returns the array of licenses specified in project function call.

 

meson.project_license_files()

SYNOPSIS

array[file] meson.project_license_files()

since 1.1.0

DESCRIPTION

Returns the array of license files specified in the project function call.

 

meson.project_name()

SYNOPSIS

str meson.project_name()

DESCRIPTION

Returns the project name specified in the project function call.

 

meson.project_source_root()

SYNOPSIS

str meson.project_source_root()

since 0.56.0

DESCRIPTION

Returns a string with the absolute path to the source root directory of the current (sub)project.

 

meson.project_version()

SYNOPSIS

str meson.project_version()

DESCRIPTION

Returns the version string specified in project function call.

 

meson.source_root()

SYNOPSIS

str meson.source_root()

deprecated since 0.56.0

DESCRIPTION

Returns a string with the absolute path to the source root directory.

This function will return the source root of the parent project if called from a subproject, which is usually not what you want. Try using meson.current_source_dir or meson.project_source_root. In the rare cases where the root of the main project is needed, use meson.global_source_root that has the same behaviour but with a more explicit name.

NOTES

You should use the files function to refer to files in the root source directory instead of constructing paths manually with meson.source_root.

 

meson.version()

SYNOPSIS

str meson.version()

DESCRIPTION

Return a string with the version of Meson.

 

module.found()

SYNOPSIS

bool module.found()

since 0.59.0

DESCRIPTION

Returns `true` if the module was successfully imported, otherwise `false`.

 

runresult.compiled()

SYNOPSIS

bool runresult.compiled()

DESCRIPTION

If `true`, the compilation succeeded, if `false` it did not and the other methods return unspecified data. This is only available for `compiler.run()` results.

 

runresult.returncode()

SYNOPSIS

int runresult.returncode()

DESCRIPTION

The return code of executing the compiled binary

 

runresult.stderr()

SYNOPSIS

str runresult.stderr()

DESCRIPTION

The standard error produced when the command was run.

 

runresult.stdout()

SYNOPSIS

str runresult.stdout()

DESCRIPTION

The standard out produced when the command was run.

 

str.contains()

SYNOPSIS

bool str.contains(fragment)

DESCRIPTION

Returns `true` if string contains the string specified as the argument.

POSARGS

fragment str, required

The string fragment to check

EXAMPLE

target = 'x86_FreeBSD'
is_fbsd = target.to_lower().contains('freebsd')
# is_fbsd now has the boolean value 'true'

 

str.endswith()

SYNOPSIS

bool str.endswith(fragment)

DESCRIPTION

Returns true if string ends with the string specified as the argument.

POSARGS

fragment str, required

The string fragment to check

EXAMPLE

target = 'x86_FreeBSD'
is_bsd = target.to_lower().endswith('bsd') # boolean value 'true'

 

str.format()

SYNOPSIS

str str.format(fmt, value...)

DESCRIPTION

Strings can be built using the string formatting functionality.

See the Meson syntax entry[43] for more information.

Since 1.3.0 values other than strings, integers, bools, options, dictionaries and lists thereof are deprecated. They were previously printing the internal representation of the raw Python object.

POSARGS

fmt str, required

The string to format.

The formatting works by replacing placeholders of type `@number@` with the corresponding varargs.

VARARGS

value int | bool | str, 0...N times

The values to replace the @number@ placeholders in the format string.

EXAMPLE

template = 'string: @0@, number: @1@, bool: @2@'
res = template.format('text', 1, true)
# res now has value 'string: text, number: 1, bool: true'

 

str.join()

SYNOPSIS

str str.join(strings...)

DESCRIPTION

The opposite of split, for example `'.'.join(['a', 'b', 'c'])` yields `'a.b.c'`.

VARARGS

strings str, 0...N times, since 0.60.0

The strings to join with the current string.

Before Meson 0.60.0 this function only accepts a single positional argument of the type array[str].

EXAMPLE

# Similar to the Python str.join()
output = ' '.join(['foo', 'bar'])
# Output value is 'foo bar'
pathsep = ':'
path = pathsep.join(['/usr/bin', '/bin', '/usr/local/bin'])
# path now has the value '/usr/bin:/bin:/usr/local/bin'

 

str.replace()

SYNOPSIS

str str.replace(old, new)

since 0.58.0

DESCRIPTION

Search all occurrences of `old` and replace it with `new`

POSARGS

old str, required

The substring to search

new str, required

The replacement string

EXAMPLE

# Replaces all instances of one substring with another
s = 'semicolons;as;separators'
s = s.replace('as', 'are')
# 's' now has the value of 'semicolons;are;separators'

 

str.split()

SYNOPSIS

array[str] str.split([split_string])

DESCRIPTION

Splits the string at the specified character (or whitespace if not set) and returns the parts in an array.

OPTARGS

split_string str

Specifies the character / substring where to split the string.

EXAMPLE

# Similar to the Python str.split()
components = 'a b c d '.split()
# components now has the value ['a', 'b', 'c', 'd']
components = 'a b c d '.split(' ')
# components now has the value ['a', 'b', '', '', 'c', 'd', '']

 

str.splitlines()

SYNOPSIS

array[str] str.splitlines()

since 1.2.0

DESCRIPTION

Splits the string into an array of lines. Unlike .split('), the empty string produced an empty array, and if the string ends in a newline, splitlines() doesn't split on that last newline. ', '' and ' are all considered newlines.

EXAMPLE

output = 'helloorld.splitlines()
# Output value is ['hello', 'world']
output = ''.splitlines()
# Output value is []
fs = import('fs')
paths = fs.read('my_paths.list').splitlines()
# paths is now the paths listed in 'my_paths.list', or an empty list
# if 'my_paths.list' is empty

 

str.startswith()

SYNOPSIS

bool str.startswith(fragment)

DESCRIPTION

Returns true if string starts with the string specified as the argument.

POSARGS

fragment str, required

The string fragment to check

EXAMPLE

target = 'x86_FreeBSD'
is_x86 = target.startswith('x86') # boolean value 'true'

 

str.strip()

SYNOPSIS

str str.strip([strip_chars])

DESCRIPTION

Removes leading/ending characters from the string.

By default the characters to remove are spaces and newlines.

OPTARGS

strip_chars str, since 0.43.0

Instead of whitespace, strip all the characters in this string.

EXAMPLE

# Similar to the Python str.strip(). Removes leading/ending spaces and newlines
define = '-Dsomedefine '
stripped_define = define.strip()
# 'stripped_define' now has the value -Dsomedefine'

 

str.substring()

SYNOPSIS

str str.substring([start], [end])

since 0.56.0

DESCRIPTION

Returns a substring specified from `start` to `end`. Both `start` and `end` arguments are optional, so, for example, `'foobar'.substring()` will return `'foobar'`.

The method accepts negative values where negative `start` is relative to the end of string `len(string)- start` as well as negative `end`.

If `start` or `end` are out of bounds, the position of the closest character will be used. If `start` is bigger than `end`, the result will be an empty substring.

OPTARGS

start int

The start position

end int

The end position

EXAMPLE

# Similar to the Python str[start:end] syntax
target = 'x86_FreeBSD'
platform = target.substring(0, 3) # prefix string value 'x86'
system = target.substring(4) # suffix string value 'FreeBSD'

Example with negative values:

string = 'foobar'
string.substring-5,-3) # => 'oo'
string.substring(1,-1) # => 'ooba'

Example with out of bound values:

string = 'foobar'
string.substring(64) # => ''
string.substring(0, 64) # => 'foobar'
string.substring(64, 0) # => ''

 

str.to_int()

SYNOPSIS

int str.to_int()

DESCRIPTION

Converts the string to an int and throws an error if it can't be

EXAMPLE

version = '1'
# Converts the string to an int and throws an error if it can't be
ver_int = version.to_int()

 

str.to_lower()

SYNOPSIS

str str.to_lower()

DESCRIPTION

Converts all characters to lower case

EXAMPLE

target = 'x86_FreeBSD'
lower = target.to_lower() # t now has the value 'x86_freebsd'

 

str.to_upper()

SYNOPSIS

str str.to_upper()

DESCRIPTION

Converts all characters to upper case

EXAMPLE

target = 'x86_FreeBSD'
upper = target.to_upper() # t now has the value 'X86_FREEBSD'

 

str.underscorify()

SYNOPSIS

str str.underscorify()

DESCRIPTION

Creates a string where every no-alphabetical no-number character is replaced with `_`.

EXAMPLE

name = 'Meson Docs.txt#Referenc-manual'
# Replaces all characters other than `-z-Z-9` with `_` (underscore)
# Useful for substituting into #defines, filenames, etc.
underscored = name.underscorify()
# underscored now has the value 'Meson_Docs_txt_Reference_manual'

 

str.version_compare()

SYNOPSIS

bool str.version_compare(compare_string)

DESCRIPTION

Does semantic version comparison.

POSARGS

compare_string str, required

The string to compare to.

EXAMPLE

version = '1.2.3'
# Compare version numbers semantically
is_new = version.version_compare('>=2.0')
# is_new now has the boolean value false
# Supports the following operators: '>', '<', '>=', '<=', '!=', '==', '='

Meson version comparison conventions include:

'3.6'.version_compare('>=3.6.0') == false

It is best to be unambiguous and specify the full revision level to compare.

Since 1.8.0 multiple versions can be compared:

'3.6'.version_compare('>=3', '<4.0') == true

 

subproject.found()

SYNOPSIS

bool subproject.found()

since 0.48.0

DESCRIPTION

Returns whether the subproject was successfully setup.

 

subproject.get_variable()

SYNOPSIS

any subproject.get_variable(var_name, [fallback])

DESCRIPTION

fetches the specified variable from inside the subproject. This is useful to, for instance, get a declare_dependency from the subproject[29].

If the variable does not exist, the variable `fallback` is returned. If a fallback is not specified, then attempting to read a no-existing variable will cause a fatal error.

POSARGS

var_name str, required

The name of the variable to query

OPTARGS

fallback any

The fallback value to return if `var_name` does not exist.

 

OBJECTS

 

alias_tgt

extends: tgt
returned_by: alias_target

Opaque object returned by alias_target.

 

any

returned_by: get_variable, get, get, get_cross_property, get_external_property, get_variable

A placeholder representing all types. This includes builtin, as well as returned objects.

 

array

returned_by: files, get_option, flatten, slice, keys, cmd_array, first_supported_argument, first_supported_link_argument, get_supported_arguments, get_supported_function_attributes, get_supported_link_arguments, preprocess, to_list, keys, values, cmd_array, project_license, project_license_files, split, splitlines

An array of elements. See arrays[44].

 

bool

returned_by: add_languages, get_option, is_disabler, is_variable, contains, found, get, get_unquoted, has, check_header, compiles, has_argument, has_define, has_function, has_function_attribute, has_header, has_header_symbol, has_link_argument, has_member, has_members, has_multi_arguments, has_multi_link_arguments, has_type, links, symbols_have_underscore_prefix, found, has_key, found, found, allowed, auto, disabled, enabled, is_even, is_odd, can_run_host_binaries, has_exe_wrapper, has_external_property, is_cross_build, is_subproject, is_unity, found, compiled, contains, endswith, startswith, version_compare, found

A boolean object which is either `true` or `false`

 

both_libs

since 0.46.0
extends: lib
returned_by: both_libraries

Container for both a static and shared library.

 

build_machine

extended_by: host_machine, target_machine

Provides information about the build machine- the machine that is doing the actual compilation. See Cros-compilation[40].

Currently, these values are populated using `platform.system()`[45] and `platform.machine()`[46]. If you think the returned values for any of these are incorrect for your system or CPU, or if your OS is not in the linked table, please file a bug[47] report with details and we'll look into it.

 

build_tgt

extends: tgt
returned_by: build_target, shared_module
extended_by: exe, jar, lib

A build target is either an executable, shared library, static library, both shared and static library or shared module.

 

cfg_data

returned_by: configuration_data

This object encapsulates configuration values to be used for generating configuration files. A more i-depth description can be found in the the configuration wiki page[10].

 

cmake

The CMake module

 

cmake_options

since 0.55.0
returned_by: subproject_options

Central configuration object for CMake subprojects

 

compiler

returned_by: get_compiler

This object is returned by meson.get_compiler. It represents a compiler for a given language and allows you to query its properties.

NOTES

These compiler checks do not use compiler arguments added with `add_*_arguments()`, via -Dlang_args` on the comman-line, or through `CFLAGS`/`LDFLAGS`, etc in the environment. Hence, you can trust that the tests will be fully sel-contained, and won't fail because of custom flags added by other parts of the build file or by users. Note that if you have a single prefix with all your dependencies, you might find it easier to append to the environment variables `C_INCLUDE_PATH` with GCC/Clang and `INCLUDE` with MSVC to expand the default include path, and `LIBRARY_PATH` with GCC/Clang and `LIB` with MSVC to expand the default library search path.

However, with GCC, these variables will be ignored when cros-compiling. In that case you need to use a specs file. See: http://www.mingw.org/wiki/SpecsFileHOWTO

 

custom_idx

returned_by: [index]

References a specific output file of a custom_tgt object.

 

custom_tgt

extends: tgt
returned_by: custom_target, vcs_tag

This object is returned by custom_target and contains a target with the following methods:

 

dep

returned_by: declare_dependency, dependency, find_library, as_link_whole, as_shared, as_static, as_system, partial_dependency

Abstract representation of a dependency

 

dict

since 0.47.0

Stores a mapping of strings to other objects. See dictionaries[48].

You can also iterate over dictionaries with the `foreach` statement[34].

(since 0.48.0): Dictionaries can be added (e.g. `d1 = d2 + d3` and `d1 += d2`). Values from the second dictionary overrides values from the first. (since 0.62.0): Dictionary order is guaranteed to be insertion order.

 

disabler

returned_by: disabler

A disabler object is an object that behaves in much the same way as NaN numbers do in floating point math. That is when used in any statement (function call, logical op, etc) they will cause the statement evaluation to immediately short circuit to return a disabler object. A disabler object has one method:

 

env

returned_by: environment

This object is returned by environment and stores detailed information about how environment variables should be set. It should be passed as the `env` keyword argument to tests and other functions.

Since 0.58.0 env.append and env.prepend can be called multiple times on the same `varname`. Earlier Meson versions would warn and only the last operation took effect.

EXAMPLE

env = environment()

# MY_PATH will be '0:1:2:3'
env.set('MY_PATH', '1')
env.append('MY_PATH', '2')
env.append('MY_PATH', '3')
env.prepend('MY_PATH', '0')

 

exe

extends: build_tgt
returned_by: executable

An executable

 

external_program

returned_by: find_program

Opaque object representing an external program

 

extracted_obj

returned_by: extract_all_objects, extract_objects

Opaque object representing extracted object files from build targets

 

feature

since 0.47.0
returned_by: get_option, disable_auto_if, disable_if, enable_auto_if, enable_if, require

Meson object representing a `feature` options[0]

 

file

returned_by: configure_file, vala_gir, vala_header, vala_vapi

Object that stores the path to an existing file

 

generated_list

returned_by: process

Opaque object representing the result of a generator.process call.

 

generator

returned_by: generator

This object is returned by generator and contains a generator that is used to transform files from one type to another by an executable (e.g. `idl` files into source code and headers).

 

host_machine

extends: build_machine

Provides information about the host machine- the machine on which the compiled binary will run. See Cros-compilation[40].

It has the same methods as build_machine.

When not cros-compiling, all the methods return the same values as build_machine (because the build machine is the host machine)

Note that while cros-compiling, it simply returns the values defined in the cros-info file.

 

inc

returned_by: include_directories, private_dir_include

Opaque wrapper for storing include directories

 

int

returned_by: get_option, length, to_int, get, get_unquoted, alignment, compute_int, sizeof, returncode, to_int

All integer numbers. See Numbers[49] for more information.

 

jar

extends: build_tgt
returned_by: jar

A Java JAR build target

 

lib

extends: build_tgt
returned_by: library, shared_library, static_library, get_shared_lib, get_static_lib
extended_by: both_libs

Represents either a shared or static library

 

meson

The `meson` object allows you to introspect various properties of the system. This object is always mapped in the `meson` variable.

 

module

returned_by: import

Base type for all modules.

Modules provide their own specific implementation methods, but all modules provide the following methods:

 

range

since 0.58.0
returned_by: range

Opaque object that can be used in a loop and accessed via `[num]`.

 

run_tgt

extends: tgt
returned_by: run_target

Opaque object returned by run_target.

 

runresult

returned_by: run_command, run

This object encapsulates the result of trying to compile and run a sample piece of code with compiler.run or run_command.

 

str

returned_by: get_option, join_paths, to_string, cpu, cpu_family, endian, kernel, subsystem, system, full_path, name, path, get, get_unquoted, get_argument_syntax, get_define, get_id, get_linker_id, version, full_path, full_path, get_configtool_variable, get_pkgconfig_variable, get_variable, include_type, name, type_name, version, full_path, path, version, full_path, to_string, backend, build_options, build_root, current_build_dir, current_source_dir, global_build_root, global_source_root, project_build_root, project_name, project_source_root, project_version, source_root, version, stderr, stdout, format, join, replace, strip, substring, to_lower, to_upper, underscorify

All strings[50] have the following methods. Strings are immutable, all operations return their results as a new string.

 

structured_src

returned_by: structured_sources

Opaque object returned by structured_sources.

 

subproject

returned_by: subproject

This object is returned by subproject and is an opaque object representing it.

 

target_machine

extends: build_machine

Provides information about the target machine- the machine on which the compiled binary's output will run. Hence, this object should only be used while cros-compiling a compiler. See Cros-compilation[40].

It has the same methods as build_machine.

When all compilation is 'native', all the methods return the same values as build_machine (because the build machine is the host machine and the target machine).

Note that while cros-compiling, it simply returns the values defined in the cros-info file. If `target_machine` values are not defined in the cros-info file, `host_machine` values are returned instead.

 

tgt

extended_by: alias_tgt, build_tgt, custom_tgt, run_tgt

Opaque base object for all Meson targets

 

void

returned_by: add_global_arguments, add_global_link_arguments, add_project_arguments, add_project_dependencies, add_project_link_arguments, add_test_setup, assert, benchmark, debug, error, install_data, install_emptydir, install_headers, install_man, install_subdir, install_symlink, message, project, set_variable, subdir, subdir_done, summary, test, unset_variable, warning, merge_from, set, set10, set_quoted, add_cmake_defines, append, prepend, set, unset, add_devenv, add_dist_script, add_install_script, add_postconf_script, install_dependency_manifest, override_dependency, override_find_program

Indicates that the function does not return anything. Similar to `void` in C and C++

 

SEE ALSO

[1] Buil-options.md#features
[2] Uni-tests.md
[3] https://www.testanything.org/
[4] https://ninj-build.org/manual.html#ref_dependencies
[5] https://ninj-build.org/manual.html#ref_headers
[6] https://dlang.org/spec/version.html#version
[7] https://gcc.gnu.org/wiki/Visibility
[8] Snippet-module.md#symbol_visibility_header
[9] Rus-module.md#proc_macro
[10] https://docs.microsoft.com/e-us/cpp/build/reference/subsyste-specif-subsystem
[11] Configuration.md
[12] https://docs.python.org/3/library/codecs.html#standar-encodings
[13] Custo-buil-targets.md#detail-o-comman-invocation
[14] https://ninj-build.org/manual.html#_the_literal_console_literal_pool
[15] Dependencies.md#cmake
[16] Dependencies.md#dependencie-wit-custo-looku-functionality
[17] Wra-dependenc-syste-manual.md#provid-section
[18] Dependencies.md#dependencie-wit-custo-looku-functionality
[19] Builti-options.md#cor-options
[20] Machin-files.md#binaries
[21] Buil-options.md
[22] Builti-options.md#universa-options
[23] Installing.md
[24] Builti-options.md#specifyin-option-pe-machine
[25] https://mesonbuild.com/Builti-options.html
[26] Builti-options.md#compile-options
[27] https://spdx.dev/ids/
[28] https://spdx.org/licenses/
[29] Externa-commands.md
[30] Subprojects.md
[31] http://man7.org/linux/ma-pages/man3/mallopt.3.html
[32] Referenc-tables.md#cp-families
[33] Referenc-tables.md#kerne-name-sinc-120
[34] Referenc-tables.md#operatin-syste-names
[35] Syntax.md#foreac-statements
[36] Referenc-tables.md#compile-ids
[37] Referenc-tables.md#linke-ids
[38] Referenc-tables.md#gc-__attribute__
[39] Commands.md#devenv
[40] Referenc-tables.md#languag-argument-paramete-names
[41] Cros-compilation.md
[42] Unit-builds.md
[43] Syntax.md#strin-formatting
[44] Syntax.md#arrays
[45] https://docs.python.org/3.7/library/platform.html#platform.system
[46] https://docs.python.org/3.7/library/platform.html#platform.machine
[47] https://github.com/mesonbuild/meson/issues/new
[48] Syntax.md#dictionaries
[49] Syntax.md#numbers
[50] Syntax.md#strings

---

 

Index

NAME

DESCRIPTION

FUNCTIONS

add_global_arguments()

add_global_link_arguments()

add_languages()

add_project_arguments()

add_project_dependencies()

add_project_link_arguments()

add_test_setup()

alias_target()

assert()

benchmark()

both_libraries()

build_target()

configuration_data()

configure_file()

custom_target()

debug()

declare_dependency()

dependency()

disabler()

environment()

error()

executable()

files()

find_program()

generator()

get_option()

get_variable()

import()

include_directories()

install_data()

install_emptydir()

install_headers()

install_man()

install_subdir()

install_symlink()

is_disabler()

is_variable()

jar()

join_paths()

library()

message()

project()

range()

run_command()

run_target()

set_variable()

shared_library()

shared_module()

static_library()

structured_sources()

subdir()

subdir_done()

subproject()

summary()

test()

unset_variable()

vcs_tag()

warning()

array.contains()

array.flatten()

array.get()

array.length()

array.slice()

bool.to_int()

bool.to_string()

both_libs.get_shared_lib()

both_libs.get_static_lib()

build_machine.cpu()

build_machine.cpu_family()

build_machine.endian()

build_machine.kernel()

build_machine.subsystem()

build_machine.system()

build_tgt.extract_all_objects()

build_tgt.extract_objects()

build_tgt.found()

build_tgt.full_path()

build_tgt.name()

build_tgt.path()

build_tgt.private_dir_include()

build_tgt.vala_gir()

build_tgt.vala_header()

build_tgt.vala_vapi()

cfg_data.get()

cfg_data.get_unquoted()

cfg_data.has()

cfg_data.keys()

cfg_data.merge_from()

cfg_data.set()

cfg_data.set10()

cfg_data.set_quoted()

cmake.subproject_options()

cmake_options.add_cmake_defines()

compiler.alignment()

compiler.check_header()

compiler.cmd_array()

compiler.compiles()

compiler.compute_int()

compiler.find_library()

compiler.first_supported_argument()

compiler.first_supported_link_argument()

compiler.get_argument_syntax()

compiler.get_define()

compiler.get_id()

compiler.get_linker_id()

compiler.get_supported_arguments()

compiler.get_supported_function_attributes()

compiler.get_supported_link_arguments()

compiler.has_argument()

compiler.has_define()

compiler.has_function()

compiler.has_function_attribute()

compiler.has_header()

compiler.has_header_symbol()

compiler.has_link_argument()

compiler.has_member()

compiler.has_members()

compiler.has_multi_arguments()

compiler.has_multi_link_arguments()

compiler.has_type()

compiler.links()

compiler.preprocess()

compiler.run()

compiler.sizeof()

compiler.symbols_have_underscore_prefix()

compiler.version()

custom_idx.full_path()

custom_tgt.[index]()

custom_tgt.full_path()

custom_tgt.to_list()

dep.as_link_whole()

dep.as_shared()

dep.as_static()

dep.as_system()

dep.found()

dep.get_configtool_variable()

dep.get_pkgconfig_variable()

dep.get_variable()

dep.include_type()

dep.name()

dep.partial_dependency()

dep.type_name()

dep.version()

dict.get()

dict.has_key()

dict.keys()

dict.values()

disabler.found()

env.append()

env.prepend()

env.set()

env.unset()

external_program.cmd_array()

external_program.found()

external_program.full_path()

external_program.path()

external_program.version()

feature.allowed()

feature.auto()

feature.disable_auto_if()

feature.disable_if()

feature.disabled()

feature.enable_auto_if()

feature.enable_if()

feature.enabled()

feature.require()

file.full_path()

generator.process()

int.is_even()

int.is_odd()

int.to_string()

meson.add_devenv()

meson.add_dist_script()

meson.add_install_script()

meson.add_postconf_script()

meson.backend()

meson.build_options()

meson.build_root()

meson.can_run_host_binaries()

meson.current_build_dir()

meson.current_source_dir()

meson.get_compiler()

meson.get_cross_property()

meson.get_external_property()

meson.global_build_root()

meson.global_source_root()

meson.has_exe_wrapper()

meson.has_external_property()

meson.install_dependency_manifest()

meson.is_cross_build()

meson.is_subproject()

meson.is_unity()

meson.override_dependency()

meson.override_find_program()

meson.project_build_root()

meson.project_license()

meson.project_license_files()

meson.project_name()

meson.project_source_root()

meson.project_version()

meson.source_root()

meson.version()

module.found()

runresult.compiled()

runresult.returncode()

runresult.stderr()

runresult.stdout()

str.contains()

str.endswith()

str.format()

str.join()

str.replace()

str.split()

str.splitlines()

str.startswith()

str.strip()

str.substring()

str.to_int()

str.to_lower()

str.to_upper()

str.underscorify()

str.version_compare()

subproject.found()

subproject.get_variable()

OBJECTS

alias_tgt

any

array

bool

both_libs

build_machine

build_tgt

cfg_data

cmake

cmake_options

compiler

custom_idx

custom_tgt

dep

dict

disabler

env

exe

external_program

extracted_obj

feature

file

generated_list

generator

host_machine

inc

int

jar

lib

meson

module

range

run_tgt

runresult

str

structured_src

subproject

target_machine

tgt

void

SEE ALSO