llvm-project/llvm/autoconf/m4/cxx_flag_check.m4

AC_DEFUN([CXX_FLAG_CHECK],
  [AC_SUBST($1, `$CXX -Werror patsubst($2, [^-Wno-], [-W]) -fsyntax-only -xc /dev/null 2>/dev/null && echo $2`)])
Add an autoconf test to check for optional compiler flags like -Wno-missing-field-initializers or -Wno-variadic-macros. llvm-svn: 85147 2009-10-27 03:58:44 +08:00			`AC_DEFUN([CXX_FLAG_CHECK],`
configure: when performing a compiler feature test for a -Wno-foo flag, attempt to use -Wfoo instead of -Wno-foo. This works around a bug in some versions of gcc, where it will silently accept an unknown -Wno-foo option, but will generate an error for a compile which uses -Wno-foo if that compile also triggers any warnings. llvm-svn: 174770 2013-02-09 06:55:10 +08:00			[AC_SUBST($1, `$CXX -Werror patsubst($2, [^-Wno-], [-W]) -fsyntax-only -xc /dev/null 2>/dev/null && echo $2`)])