When on darwin, compiler_flags need to be percolated down to the 'gcc -r'

command line so that relinked .o files can be built universal.

llvm-svn: 27837

llvm/autoconf/m4/libtool.m4

@@ -2099,7 +2099,7 @@ reload_cmds='$LD$reload_flag -o $output$reload_objs'
 case $host_os in
   darwin*)
     if test "$GCC" = yes; then
-      reload_cmds='$CC -nostdlib ${wl}-r -o $output$reload_objs'
+      reload_cmds='$CC -nostdlib ${wl}-r $compiler_flags -o $output$reload_objs'
     else
       reload_cmds='$LD$reload_flag -o $output$reload_objs'
     fi