Fix libcxxabi tests after clang r334924

git-svn-id: https://llvm.org/svn/llvm-project/libcxxabi/trunk@334926 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/libcxxabi/test/config.py b/test/libcxxabi/test/config.py
index 9f8724c..abec67f 100644
--- a/test/libcxxabi/test/config.py
+++ b/test/libcxxabi/test/config.py
@@ -35,7 +35,7 @@
         super(Configuration, self).configure_obj_root()
 
     def has_cpp_feature(self, feature, required_value):
-        return intMacroValue(self.cxx.dumpMacros().get('__cpp_' + feature, 0)) >= required_value
+        return intMacroValue(self.cxx.dumpMacros().get('__cpp_' + feature, '0')) >= required_value
 
     def configure_features(self):
         super(Configuration, self).configure_features()