project('preprocess', 'c') cc = meson.get_compiler('c') add_project_arguments(['-DFOO=0', '-DBAR=0'], language: 'c') pp_files = cc.preprocess('foo.c', 'bar.c', output: '@PLAINNAME@') foreach f : pp_files message(f.full_path()) endforeach subdir('src') test('test-foo', executable('app', pp_files, link_depends: file_map))