--- isl-0.14/isl_ast.c.orig	2014-12-04 10:19:12.262314510 +0100
+++ isl-0.14/isl_ast.c	2014-12-04 10:19:58.317312916 +0100
@@ -358,6 +358,8 @@
 		return 1;
 	case isl_ast_expr_error:
 		return -1;
+	default:
+		return -1;
 	}
 }