With 57ec9254eb (docs: introduce document to announce breaking changes,
2024-06-14), we have introduced a new document that tracks upcoming
breaking changes in the Git project. In 2454970930 (BreakingChanges:
early adopter option, 2024-10-11) we have amended the document a bit to
mention that any introduced breaking changes must be accompanied by
logic that allows us to enable the breaking change at compile-time.
While we already have two breaking changes lined up, neither of them has
such a switch because they predate those instructions.
Introduce the proposed `WITH_BREAKING_CHANGES` preprocessor macro and
wire it up with both our Makefiles and Meson. This does not yet wire up
the build flag for existing deprecations.
Signed-off-by: Patrick Steinhardt <ps@xxxxxx>
---
GIT-BUILD-OPTIONS.in | 1 +
Makefile | 5 +++++
contrib/buildsystems/CMakeLists.txt | 1 +
meson.build | 6 ++++++
meson_options.txt | 2 ++
t/test-lib.sh | 4 ++++
6 files changed, 19 insertions(+)
diff --git a/GIT-BUILD-OPTIONS.in b/GIT-BUILD-OPTIONS.in
index f651116102..f1d0ecf123 100644
--- a/GIT-BUILD-OPTIONS.in
+++ b/GIT-BUILD-OPTIONS.in
@@ -45,3 +45,4 @@ GITWEBDIR=@GITWEBDIR@
USE_GETTEXT_SCHEME=@USE_GETTEXT_SCHEME@
LOCALEDIR=@LOCALEDIR@
BROKEN_PATH_FIX=@BROKEN_PATH_FIX@
+WITH_BREAKING_CHANGES=@WITH_BREAKING_CHANGES@
diff --git a/Makefile b/Makefile
index 06f01149ec..dc3c980aa7 100644
--- a/Makefile
+++ b/Makefile
@@ -2230,6 +2230,10 @@ ifdef FSMONITOR_OS_SETTINGS
COMPAT_OBJS += compat/fsmonitor/fsm-path-utils-$(FSMONITOR_OS_SETTINGS).o
endif
+ifdef WITH_BREAKING_CHANGES
+ BASIC_CFLAGS += -DWITH_BREAKING_CHANGES
+endif
+
ifeq ($(TCLTK_PATH),)
NO_TCLTK = NoThanks
endif
@@ -3187,6 +3191,7 @@ GIT-BUILD-OPTIONS: FORCE
-e "s|@USE_GETTEXT_SCHEME@|\'$(USE_GETTEXT_SCHEME)\'|" \
-e "s|@LOCALEDIR@|\'$(localedir_SQ)\'|" \
-e "s!@BROKEN_PATH_FIX@!\'$(BROKEN_PATH_FIX)\'!" \
+ -e "s|@WITH_BREAKING_CHANGES@|\'$(WITH_BREAKING_CHANGES)\'|" \
GIT-BUILD-OPTIONS.in >$@+
@if grep -q '^[A-Z][A-Z_]*=@.*@$$' $@+; then echo "Unsubstituted build options in $@" >&2 && exit 1; fi
@if cmp $@+ $@ >/dev/null 2>&1; then $(RM) $@+; else mv $@+ $@; fi
diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
index 49904ca8a9..63d0088928 100644
--- a/contrib/buildsystems/CMakeLists.txt
+++ b/contrib/buildsystems/CMakeLists.txt
@@ -1198,6 +1198,7 @@ string(REPLACE "@GITWEBDIR@" "'${GITWEBDIR}'" git_build_options "${git_build_opt
string(REPLACE "@USE_GETTEXT_SCHEME@" "" git_build_options "${git_build_options}")
string(REPLACE "@LOCALEDIR@" "'${LOCALEDIR}'" git_build_options "${git_build_options}")
string(REPLACE "@BROKEN_PATH_FIX@" "" git_build_options "${git_build_options}")
+string(REPLACE "@WITH_BREAKING_CHANGES@" "" git_build_options "${git_build_options}")
if(USE_VCPKG)
string(APPEND git_build_options "PATH=\"$PATH:$TEST_DIRECTORY/../compat/vcbuild/vcpkg/installed/x64-windows/bin\"\n")
endif()
diff --git a/meson.build b/meson.build
index 0dccebcdf1..316cd93264 100644
--- a/meson.build
+++ b/meson.build
@@ -644,6 +644,12 @@ build_options_config.set('GIT_TEST_UTF8_LOCALE', '')
build_options_config.set_quoted('LOCALEDIR', fs.as_posix(get_option('prefix') / get_option('localedir')))
build_options_config.set('GITWEBDIR', fs.as_posix(get_option('prefix') / get_option('datadir') / 'gitweb'))
+if get_option('breaking_changes')
+ build_options_config.set('WITH_BREAKING_CHANGES', 'YesPlease')
+else
+ build_options_config.set('WITH_BREAKING_CHANGES', '')
+endif
+
if get_option('sane_tool_path') != ''
build_options_config.set_quoted('BROKEN_PATH_FIX', 's|^\# @BROKEN_PATH_FIX@$|git_broken_path_fix "' + get_option('sane_tool_path') + '"|')
else
diff --git a/meson_options.txt b/meson_options.txt
index 32a72139ba..800e518d95 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -43,6 +43,8 @@ option('sha256_backend', type: 'combo', choices: ['openssl', 'nettle', 'gcrypt',
description: 'The backend used for hashing objects with the SHA256 object format')
# Build tweaks.
+option('breaking_changes', type: 'boolean', value: false,
+ description: 'Enable upcoming breaking changes.')
option('macos_use_homebrew_gettext', type: 'boolean', value: true,
description: 'Use gettext from Homebrew instead of the slightly-broken system-provided one.')
diff --git a/t/test-lib.sh b/t/test-lib.sh
index 62dfcc4aaf..6e423f655d 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -1864,6 +1864,10 @@ test_lazy_prereq CURL '
curl --version
'
+test_lazy_prereq WITHOUT_BREAKING_CHANGES '
+ test -z "$WITH_BREAKING_CHANGES"
+'
+
# SHA1 is a test if the hash algorithm in use is SHA-1. This is both for tests
# which will not work with other hash algorithms and tests that work but don't
# test anything meaningful (e.g. special values which cause short collisions).
--
2.48.0.257.gd3603152ad.dirty
