Seemingly that at some point clang started accepting _any_ flags, whereas previously it would error out.
These days, you can give it -Whamsandwich and it will succeed, while at the same time throwing an annoying warning. Add -Werror so that everything gets flagged and set accordingly. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108082 Cc: Eric Engestrom <eric.engest...@intel.com> Cc: Dylan Baker <dy...@pnwbakers.com> Cc: Vinson Lee <v...@freedesktop.org> Repored-by: Vinson Lee <v...@freedesktop.org> Signed-off-by: Emil Velikov <emil.veli...@collabora.com> --- m4/ax_check_compile_flag.m4 | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/m4/ax_check_compile_flag.m4 b/m4/ax_check_compile_flag.m4 index 51df0c09a7a..0fdca907e8b 100644 --- a/m4/ax_check_compile_flag.m4 +++ b/m4/ax_check_compile_flag.m4 @@ -55,6 +55,11 @@ # modified version of the Autoconf Macro, you may extend this special # exception to the GPL to apply to your modified version as well. +# Emil: +# Toggle Werror since at some point clang started treating unknown -W +# flags as warnings, succeeding with the build, yet issuing an annoying +# warning. + #serial 3 AC_DEFUN([AX_CHECK_COMPILE_FLAG], @@ -62,7 +67,7 @@ AC_DEFUN([AX_CHECK_COMPILE_FLAG], AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]flags_$4_$1])dnl AC_CACHE_CHECK([whether _AC_LANG compiler accepts $1], CACHEVAR, [ ax_check_save_flags=$[]_AC_LANG_PREFIX[]FLAGS - _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1" + _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1 -Werror" AC_COMPILE_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])], [AS_VAR_SET(CACHEVAR,[yes])], [AS_VAR_SET(CACHEVAR,[no])]) -- 2.19.1 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
