meson/docs/markdown/Pkgconfig-module.md

Pkgconfig module

This module is a simple generator for pkg-config files.

Usage

pkg = import('pkgconfig')
bar_dep = dependency('bar')
lib = library('foo', dependencies : [bar])
pkg.generate(lib)

pkg.generate()

The generated file's properties are specified with the following keyword arguments.

• description a string describing the library, used to set the Description: field
• extra_cflags a list of extra compiler flags to be added to the Cflags field after the header search path
• filebase the base name to use for the pkg-config file; as an example, the value of libfoo would produce a pkg-config file called libfoo.pc
• install_dir the directory to install to, defaults to the value of option libdir followed by /pkgconfig
• libraries a list of built libraries (usually results of shared_library) that the user needs to link against. Arbitrary strings can also be provided and they will be added into the Libs field. Since 0.45.0 dependencies of built libraries will be automatically added, see the Implicit dependencies section below for the exact rules. Since 0.58.0 custom_target() objects are supported as long as they are linkable (has known extension such as .a, .so, etc).
• libraries_private list of built libraries or strings to put in the Libs.private field. Since 0.45.0 dependencies of built libraries will be automatically added, see the Implicit dependencies section below for the exact rules. Since 0.58.0 custom_target() objects are supported as long as they are linkable (has known extension such as .a, .so, etc).
• name the name of this library, used to set the Name: field
• subdirs which subdirs of include should be added to the header search path, for example if you install headers into ${PREFIX}/include/foobar-1, the correct value for this argument would be foobar-1
• requires list of strings, pkgconfig-dependencies or libraries that pkgconfig.generate() was used on to put in the Requires field
• requires_private the same as requires but for the Requires.private field
• url a string with a url for the library
• variables a list of strings with custom variables to add to the generated file. The strings must be in the form name=value and may reference other pkgconfig variables, e.g. datadir=${prefix}/share. The names prefix, libdir and includedir are reserved and may not be used. Since 0.56.0 it can also be a dictionary but ordering of Meson dictionaries are not guaranteed, which could cause issues when some variables reference other variables. Spaces in values are escaped with \, this is required in the case the value is a path that and is used in cflags or libs arguments. Since 0.59.0 if escaping is not desired (e.g. space separate list of values) unescaped_variables keyword argument should be used instead. Since 0.62.0 builtin directory variables that are referenced are automatically created by default.
• uninstalled_variables used instead of the variables keyword argument, when generating the uninstalled pkg-config file. Since 0.54.0 Spaces in values are escaped with \, this is required in the case the value is a path that and is used in cflags or libs arguments. Since 0.59.0 if escaping is not desired (e.g. space separate list of values) unescaped_uninstalled_variables keyword argument should be used instead.
• version a string describing the version of this library, used to set the Version: field. (since 0.46.0) Defaults to the project version if unspecified.
• d_module_versions a list of module version flags used when compiling D sources referred to by this pkg-config file
• dataonly field. (since 0.54.0) this is used for architecture-independent pkg-config files in projects which also have architecture-dependent outputs.
• conflicts (since 0.36.0, incorrectly issued a warning prior to 0.54.0) list of strings to be put in the Conflicts field.

Since 0.46 a StaticLibrary or SharedLibrary object can optionally be passed as first positional argument. If one is provided a default value will be provided for all required fields of the pc file:

• install_dir is set to pkgconfig folder in the same location than the provided library.
• description is set to the project's name followed by the library's name.
• name is set to the library's name.

Since 0.54.0 uninstalled pkg-config files are generated as well. They are located in <build dir>/meson-uninstalled/. It is sometimes useful to build projects against libraries built by Meson without having to install them into a prefix. In order to do so, just set PKG_CONFIG_PATH=<builddir>/meson-uninstalled before building your application. That will cause pkg-config to prefer those -uninstalled.pc files and find libraries and headers from the Meson builddir. This is an experimental feature provided on a best-effort basis, it might not work in all use-cases.

Implicit dependencies

The exact rules followed to find dependencies that are implicitly added into the pkg-config file have evolved over time. Here are the rules as of Meson 0.49.0, previous versions might have slightly different behaviour.

• Not found libraries or dependencies are ignored.
• Libraries and dependencies are private by default (i.e. added into Requires.private: or Libs.private:) unless they are explicitly added in libraries or requires keyword arguments, or is the main library (first positional argument).
• Libraries and dependencies will be de-duplicated, if they are added in both public and private (e.g Requires: and Requires.private:) it will be removed from the private list.
• Shared libraries (i.e. shared_library() and NOT library()) add only -lfoo into Libs: or Libs.private: but their dependencies are not pulled. This is because dependencies are only needed for static link.
• Other libraries (i.e. static_library() or library()) add -lfoo into Libs: or Libs.private: and recursively add their dependencies into Libs.private: or Requires.private:.
• Dependencies provided by pkg-config are added into Requires: or Requires.private:. If a version was specified when declaring that dependency it will be written into the generated file too.
• The threads dependency (i.e. dependency('threads')) adds -pthread into Libs: or Libs.private:.
• Internal dependencies (i.e. declare_dependency(compiler_args : '-DFOO', link_args : '-Wl,something', link_with : foo)) add compiler_args into Cflags: if public, link_args and link_with into Libs: if public or Libs.private: if private.
• Other dependency types add their compiler arguments into Cflags: if public, and linker arguments into Libs: if public or Libs.private: if private.
• Once a pkg-config file is generated for a library using pkg.generate(mylib), any subsequent call to pkg.generate() where mylib appears, will generate a Requires: or Requires.private instead of a Libs: or Libs.private:.