Change a comment added in e208f9cc757 (make error()'s constant return value more visible, 2012-12-15) to note that the code doesn't only depend on variadic macros, which have been a hard dependency since 765dc168882 (git-compat-util: always enable variadic macros, 2021-01-28), but also on GCC's handling of __VA_ARGS__. The commit message for e208f9cc757 made this clear, but the comment it added did not. See also e05bed960d3 (trace: add 'file:line' to all trace output, 2014-07-12) for another comment about GNUC's handling of __VA_ARGS__. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> --- git-compat-util.h | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/git-compat-util.h b/git-compat-util.h index 9ddf9d7044b..540aba22a4d 100644 --- a/git-compat-util.h +++ b/git-compat-util.h @@ -480,10 +480,15 @@ void warning_errno(const char *err, ...) __attribute__((format (printf, 1, 2))); /* * Let callers be aware of the constant return value; this can help - * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though, - * because some compilers may not support variadic macros. Since we're only - * trying to help gcc, anyway, it's OK; other compilers will fall back to - * using the function as usual. + * gcc with -Wuninitialized analysis. + * + * We restrict this trick to gcc, though, because while we rely on the + * presence of C99 variadic macros, this code also relies on the + * non-standard behavior of GCC's __VA_ARGS__, allowing error() to + * work even if no format specifiers are passed to error(). + * + * Since we're only trying to help gcc, anyway, it's OK; other + * compilers will fall back to using the function as usual. */ #if defined(__GNUC__) static inline int const_error(void) -- 2.31.1.631.gb80e078001e
