@matheusbsbs / matheus-bagliano / commits / 8c3add51a8

meson: work around broken system PCRE2 dependency in macOS

macOS provides a PCRE2 library in base that is not usable and not configured properly, as it installs a pkgconf module that points to a non-existent pcre2.h header in /usr/local/include. Detect that case and if the feature is enabled, try to fallback to a wrapped subproject through an anonymous dependency, aborting with an error if that is not possible. Change the feature to "auto" and print a warning and disable it if a broken dependency was detected, but to keep consistency with the cmake build system used on Windows, add a special rule to re-enable the pcre2 feature by default there. Helped-by: Eric Sunshine <sunshine@sunshineco.com> Suggested-by: Eli Schwartz <eschwartz@gentoo.org> Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Carlo Marcelo Arenas Belón committed Jul 18, 2025 at 10:02 UTC 8c3add51a873616075baebed164eca4aa1069c51
2 files changed +28 -2
meson.build
+27 -1
@@ -1055,7 +1055,33 @@ else
1055 build_options_config.set('NO_ICONV', '1')
1056 endif
1057
1058 -pcre2 = dependency('libpcre2-8', required: get_option('pcre2'), default_options: ['default_library=static', 'test=false'])
1058 +# can't use enable_auto_if() because it is only available in meson 1.1
1059 +if host_machine.system() == 'windows' and get_option('pcre2').allowed()
1060 + pcre2_feature = true
1061 +else
1062 + pcre2_feature = get_option('pcre2')
1063 +endif
1064 +pcre2 = dependency('libpcre2-8', required: pcre2_feature, default_options: ['default_library=static', 'test=false'])
1065 +if pcre2.found() and pcre2.type_name() != 'internal' and host_machine.system() == 'darwin'
1066 + # macOS installs a broken system package, double check
1067 + if not compiler.has_header('pcre2.h', dependencies: pcre2)
1068 + if pcre2_feature.enabled()
1069 + pcre2_fallback = ['pcre2', 'libpcre2_8']
1070 + else
1071 + pcre2_fallback = []
1072 + endif
1073 + # Attempt to fallback or replace with not-found-dependency
1074 + pcre2 = dependency('', required: false, fallback: pcre2_fallback, default_options: ['default_library=static', 'test=false'])
1075 + if not pcre2.found()
1076 + if pcre2_feature.enabled()
1077 + error('only a broken pcre2 install found and pcre2 is required')
1078 + else
1079 + warning('broken pcre2 install found, disabling pcre2 feature')
1080 + endif
1081 + endif
1082 + endif
1083 +endif
1084 +
1085 if pcre2.found()
1086 libgit_dependencies += pcre2
1087 libgit_c_args += '-DUSE_LIBPCRE2'
meson_options.txt
+1 -1
@@ -45,7 +45,7 @@ option('gitweb', type: 'feature', value: 'auto',
45 description: 'Build Git web interface. Requires Perl.')
46 option('iconv', type: 'feature', value: 'auto',
47 description: 'Support reencoding strings with different encodings.')
48 -option('pcre2', type: 'feature', value: 'enabled',
48 +option('pcre2', type: 'feature', value: 'auto',
49 description: 'Support Perl-compatible regular expressions in e.g. git-grep(1).')
50 option('perl', type: 'feature', value: 'auto',
51 description: 'Build tools written in Perl.')