llvm-6502/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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85147 91177308-0d34-0410-b5e6-96231b3b80d8 2009-10-26 19:58:44 +00:00			`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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174770 91177308-0d34-0410-b5e6-96231b3b80d8 2013-02-08 22:55:10 +00:00			[AC_SUBST($1, `$CXX -Werror patsubst($2, [^-Wno-], [-W]) -fsyntax-only -xc /dev/null 2>/dev/null && echo $2`)])