Merge pull request Tencent#870 from StilesCrisis/null-handler-fix

Null handler fix

Author: miloyip

include/rapidjson/schema.h

@@ -1928,7 +1928,7 @@ RAPIDJSON_MULTILINEMACRO_END
     const Context& CurrentContext() const { return *schemaStack_.template Top<Context>(); }
 
     OutputHandler& CreateNullHandler() {
-        return *(nullHandler_ = static_cast<OutputHandler*>(GetStateAllocator().Malloc(sizeof(OutputHandler))));
+        return *(nullHandler_ = new (GetStateAllocator().Malloc(sizeof(OutputHandler))) OutputHandler);
     }
 
     static const size_t kDefaultSchemaStackCapacity = 1024;

test/unittest/schematest.cpp

@@ -1281,6 +1281,12 @@ TEST(SchemaValidatingWriter, Simple) {
     EXPECT_TRUE(validator.GetInvalidDocumentPointer() == SchemaDocument::PointerType(""));
 }
 
+TEST(Schema, Issue848) {
+    rapidjson::Document d;
+    rapidjson::SchemaDocument s(d);
+    rapidjson::GenericSchemaValidator<rapidjson::SchemaDocument, rapidjson::Document> v(s);
+}
+
 #if RAPIDJSON_HAS_CXX11_RVALUE_REFS
 
 static SchemaDocument ReturnSchemaDocument() {