X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=acinclude.m4;h=717c68166177009a8d6636d268713e2e216ddef3;hb=501948203fd12718a2372ebfb78e79f33419e10f;hp=eadc9a76b74b6d1f43fb28122ed438fb7a1059c5;hpb=eca39bced3aee7bd01dec43619e810ca2e40e459;p=sliver-openvswitch.git

diff --git a/acinclude.m4 b/acinclude.m4
index eadc9a76b..717c68166 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -362,15 +362,15 @@ dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
 
-dnl OVS_CHECK_CC_OPTION([OPTION], [ACTION-IF-ACCEPTED], [ACTION-IF-REJECTED])
-dnl Check whether the given C compiler OPTION is accepted.
-dnl If so, execute ACTION-IF-ACCEPTED, otherwise ACTION-IF-REJECTED.
-AC_DEFUN([OVS_CHECK_CC_OPTION],
-[
+AC_DEFUN([_OVS_CHECK_CC_OPTION], [dnl
   m4_define([ovs_cv_name], [ovs_cv_[]m4_translit([$1], [-], [_])])dnl
   AC_CACHE_CHECK([whether $CC accepts $1], [ovs_cv_name], 
     [ovs_save_CFLAGS="$CFLAGS"
-     CFLAGS="$CFLAGS $1"
+     dnl Include -Werror in the compiler options, because without -Werror
+     dnl clang's GCC-compatible compiler driver does not return a failure
+     dnl exit status even though it complains about options it does not
+     dnl understand.
+     CFLAGS="$CFLAGS $WERROR $1"
      AC_COMPILE_IFELSE([AC_LANG_PROGRAM(,)], [ovs_cv_name[]=yes], [ovs_cv_name[]=no])
      CFLAGS="$ovs_save_CFLAGS"])
   if test $ovs_cv_name = yes; then
@@ -380,6 +380,21 @@ AC_DEFUN([OVS_CHECK_CC_OPTION],
   fi
 ])
 
+dnl OVS_CHECK_WERROR
+dnl
+dnl Check whether the C compiler accepts -Werror.
+dnl Sets $WERROR to "-Werror", if so, and otherwise to the empty string.
+AC_DEFUN([OVS_CHECK_WERROR],
+  [WERROR=
+   _OVS_CHECK_CC_OPTION([-Werror], [WERROR=-Werror])])
+
+dnl OVS_CHECK_CC_OPTION([OPTION], [ACTION-IF-ACCEPTED], [ACTION-IF-REJECTED])
+dnl Check whether the given C compiler OPTION is accepted.
+dnl If so, execute ACTION-IF-ACCEPTED, otherwise ACTION-IF-REJECTED.
+AC_DEFUN([OVS_CHECK_CC_OPTION],
+  [AC_REQUIRE([OVS_CHECK_WERROR])
+   _OVS_CHECK_CC_OPTION([$1], [$2], [$3])])
+
 dnl OVS_ENABLE_OPTION([OPTION])
 dnl Check whether the given C compiler OPTION is accepted.
 dnl If so, add it to WARNING_FLAGS.