--- isl/m4/ax_cc_maxopt.m4.org	2011-01-08 18:12:56.000000000 -0500
+++ isl/m4/ax_cc_maxopt.m4	2011-01-08 19:20:53.000000000 -0500
@@ -151,7 +151,7 @@
      AX_GCC_ARCHFLAG($acx_maxopt_portable)
 
      # drop to -O1 for gcc 4.2
-     $CC --version |
+     $CC --version | grep -v 'Apple Inc' |
 	sed -e 's/.* \(@<:@0-9@:>@@<:@0-9@:>@*\)\.\(@<:@0-9@:>@@<:@0-9@:>@*\).*/\1 \2/' |
 	(read major minor
 	    if test $major -eq 4 -a $minor -eq 2; then