isl: Avoid a spurious symbol reference that breaks GCC build (#778).

pkgs/development/libraries/isl/default.nix

@@ -9,6 +9,7 @@ stdenv.mkDerivation rec {
   };
 
   buildInputs = [ gmp ];
+  patches = [ ./fix-gcc-build.diff ];
 
   meta = {
     homepage = http://www.kotnet.org/~skimo/isl/;

pkgs/development/libraries/isl/fix-gcc-build.diff

@@ -0,0 +1,12 @@
+diff -ru isl-0.11.1/include/isl/int.h isl-0.11.1.new/include/isl/int.h
+--- isl-0.11.1/include/isl/int.h        2012-11-29 09:47:32.000000000 +0100
++++ isl-0.11.1.new/include/isl/int.h    2013-10-27 15:35:31.348553812 +0100
+@@ -14,7 +14,7 @@
+ #include <string.h>
+ #include <gmp.h>
+ #if defined(__cplusplus)
+-#include <iostream>
++#include <ostream>
+ #endif
+ 
+ #if defined(__cplusplus)