[PATCH v6] meson: work around broken system PCRE2 dependency in macOS
From: Carlo Marcelo Arenas Belón <hidden>
Date: 2025-07-18 17:02:44
Subsystem:
the rest · Maintainer:
Linus Torvalds
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 [off-list ref] Suggested-by: Eli Schwartz <redacted> Signed-off-by: Carlo Marcelo Arenas Belón <redacted> --- meson.build | 28 +++++++++++++++++++++++++++- meson_options.txt | 2 +- 2 files changed, 28 insertions(+), 2 deletions(-)
diff --git a/meson.build b/meson.build
index 596f5ac711..5225efb4a6 100644
--- a/meson.build
+++ b/meson.build@@ -1055,7 +1055,33 @@ else build_options_config.set('NO_ICONV', '1') endif -pcre2 = dependency('libpcre2-8', required: get_option('pcre2'), default_options: ['default_library=static', 'test=false']) +# can't use enable_auto_if() because it is only available in meson 1.1 +if host_machine.system() == 'windows' and get_option('pcre2').allowed() + pcre2_feature = true +else + pcre2_feature = get_option('pcre2') +endif +pcre2 = dependency('libpcre2-8', required: pcre2_feature, default_options: ['default_library=static', 'test=false']) +if pcre2.found() and pcre2.type_name() != 'internal' and host_machine.system() == 'darwin' + # macOS installs a broken system package, double check + if not compiler.has_header('pcre2.h', dependencies: pcre2) + if pcre2_feature.enabled() + pcre2_fallback = ['pcre2', 'libpcre2_8'] + else + pcre2_fallback = [] + endif + # Attempt to fallback or replace with not-found-dependency + pcre2 = dependency('', required: false, fallback: pcre2_fallback, default_options: ['default_library=static', 'test=false']) + if not pcre2.found() + if pcre2_feature.enabled() + error('only a broken pcre2 install found and pcre2 is required') + else + warning('broken pcre2 install found, disabling pcre2 feature') + endif + endif + endif +endif + if pcre2.found() libgit_dependencies += pcre2 libgit_c_args += '-DUSE_LIBPCRE2'
diff --git a/meson_options.txt b/meson_options.txt
index e7f768df24..1668f260a1 100644
--- a/meson_options.txt
+++ b/meson_options.txt@@ -45,7 +45,7 @@ option('gitweb', type: 'feature', value: 'auto', description: 'Build Git web interface. Requires Perl.') option('iconv', type: 'feature', value: 'auto', description: 'Support reencoding strings with different encodings.') -option('pcre2', type: 'feature', value: 'enabled', +option('pcre2', type: 'feature', value: 'auto', description: 'Support Perl-compatible regular expressions in e.g. git-grep(1).') option('perl', type: 'feature', value: 'auto', description: 'Build tools written in Perl.')
--
2.39.5 (Apple Git-154)