[PATCH v4 1/3] compat/posix.h: enable UNUSED warning messages for Clang
- From
- Dominik Loidolt <dominik.loidolt@univie.ac.at>
- Date
- Jun 13, 2026, 12:27 UTC
- Message-ID
- <20260613122711.38662-2-dominik.loidolt@univie.ac.at>
- In-Reply-To
- <20260613122711.38662-1-dominik.loidolt@univie.ac.at>
Use a dedicated Clang version check for the UNUSED macro.
Commit 7c07f36ad2 (git-compat-util.h: GCC deprecated message arg only in GCC 4.5+, 2022-10-05) restricted use of the deprecated attribute's message argument in the UNUSED macro to GCC 4.5 or newer.
Clang identifies itself as GNUC 4.2.1 for compatibility, so GIT_GNUC_PREREQ(4, 5) does not detect whether Clang supports the deprecated("...") form. Add GIT_CLANG_PREREQ() macro and use it to enable the UNUSED warning message for Clang 2.9 and newer.
Signed-off-by: Dominik Loidolt <dominik.loidolt@univie.ac.at> --- compat/posix.h | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/compat/posix.h b/compat/posix.h index faaae1b655..273cb87101 100644 --- a/compat/posix.h +++ b/compat/posix.h @@ -12,6 +12,9 @@ * ... code requiring gcc 2.8 or later ... * #endif * + * Note that Clang and other compilers define __GNUC__ for compatibility; use + * GIT_CLANG_PREREQ() to check for specific Clang versions. + * * This macro of course is not part of POSIX, but we need it for the UNUSED * macro which is used by some of our POSIX compatibility wrappers. */ @@ -22,6 +25,15 @@ #define GIT_GNUC_PREREQ(maj, min) 0 #endif +/* Similar for Clang. */ +#if defined(__clang__) && defined(__clang_minor__) && defined(__clang_major__) +# define GIT_CLANG_PREREQ(maj, min) \ + ((__clang_major__ > (maj)) || \ + (__clang_major__ == (maj) && __clang_minor__ >= (min))) +#else +# define GIT_CLANG_PREREQ(maj, min) 0 +#endif + /* * UNUSED marks a function parameter that is always unused. It also * can be used to annotate a function, a variable, or a type that is @@ -35,7 +47,7 @@ * When a parameter may be used or unused, depending on conditional * compilation, consider using MAYBE_UNUSED instead. */ -#if GIT_GNUC_PREREQ(4, 5) +#if GIT_GNUC_PREREQ(4, 5) || GIT_CLANG_PREREQ(2, 9) #define UNUSED __attribute__((unused)) \ __attribute__((deprecated ("parameter declared as UNUSED"))) #elif defined(__GNUC__)
-- 2.54.0