Meson

Meson is a cross-platform build automation tool for C/C++. Its syntax is similar to Python’s, and is strongly typed but not Turing complete.

Meson requires a separate build directory for compiler outputs. It takes an order of precedence for the default C/C++ compiler: GCC/G++, LLVM (Clang, Clang++), MSVC, and so on.

We have a few commands (assume they start with meson):

• setup build — which sets up the Meson project inside the build directory. This can be a different name, it just needs to be a specific directory.
• compile -C build — which compiles the project to the build directory.

Quick links:

• Usage manual
• Function, type, object manual

Build file

The standard Meson build file is stored in meson.build. We should ideally have one in our main project directory, and more files in any sub-directories.

We need to define several characteristics in our main build file:

• project('name', 'lang') — defines a project name, and the language which determines the compiler version. We can also add extra parameters:
  • default_options : ['arr'] — allows us to specify things like language-version. For instance, we can set the c_std=gnu17 for the GNU version of C17.
• subdir('dir') should be used for any required subdirectories in the build step. Any local variables in the meson.build files in those subdirectories are usable in the parent file.
• executable('name', ['files']) — specifies the executable name and any files used to compile to it.
• dependency('lib') — specifies a single library dependency (i.e., GTK). For each dependency, we need separate dependency() calls.