Introduce InlinedGlobalMarkingVisitor

Source/wtf/TypeTraits.h

  /*
  * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2009, 2010 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 222 matching lines @@
     };
 
     template <typename T, template <class V> class OuterTemplate> struct RemoveTemplate {
         typedef T Type;
     };
 
     template <typename T, template <class V> class OuterTemplate> struct RemoveTemplate<OuterTemplate<T>, OuterTemplate> {
         typedef T Type;
     };
 
+    template <typename T> struct Identity {
+        typedef T type; 
+    };
+
     template <typename T> struct RemoveConst {
         typedef T Type;
     };
 
     template <typename T> struct RemoveConst<const T> {
         typedef T Type;
     };
 
     template <typename T> struct RemoveVolatile {
         typedef T Type;
@@ skipping 43 matching lines @@
 #define EnsurePtrConvertibleArgDecl(From, To) \
     typename WTF::EnableIf<WTF::IsPointerConvertible<From, To>::Value, bool>::Type = true
 #define EnsurePtrConvertibleArgDefn(From, To) \
     typename WTF::EnableIf<WTF::IsPointerConvertible<From, To>::Value, bool>::Type
 
 } // namespace WTF
 
 namespace blink {
 
 class JSONValue;
+class InlinedGlobalMarkingVisitor;
+class Visitor;
 
 } // namespace blink
 
 namespace WTF {
 
     // FIXME: Disable pointer conversion checking against JSONValue.
     // The current CodeGeneratorInspector.py generates code which upcasts to JSONValue from undefined types.
     template<typename From> class IsPointerConvertible<From, blink::JSONValue> {
     public:
         enum {
             Value = true
         };
     };
 
 template<typename T>
+class HasTraceNewMethod {
+    typedef char YesType;
+    typedef struct NoType {
+        char padding[8];
+    } NoType;
+#if COMPILER(MSVC)
+    QUACK!
+#else
+    template<size_t> struct HasMethod;
+    template<typename V> static YesType checkHasTraceNewMethod(HasMethod<sizeof(static_cast<void (V::*)(blink::InlinedGlobalMarkingVisitor)>(&V::trace))>*);
+#endif // COMPILER(MSVC)
+    template<typename V> static NoType checkHasTraceNewMethod(...);
+public:
+    static const bool value = sizeof(YesType) + sizeof(T) == sizeof(checkHasTraceNewMethod<T>(0)) + sizeof(T);
+};
+
+template<typename T>
 class NeedsTracing {
     typedef char YesType;
     typedef struct NoType {
         char padding[8];
     } NoType;
 #if COMPILER(MSVC)
+    QUACK!
     template<typename V> static YesType checkHasTraceMethod(char[&V::trace != 0]);
 #else
     template<size_t> struct HasMethod;
-    template<typename V> static YesType checkHasTraceMethod(HasMethod<sizeof(&V::trace)>*);
+    template<typename V> static YesType checkHasTraceMethod(HasMethod<sizeof(static_cast<void (V::*)(blink::Visitor*)>(&V::trace))>*);
 #endif // COMPILER(MSVC)
     template<typename V> static NoType checkHasTraceMethod(...);
 public:
     // We add sizeof(T) to both sides here, because we want it to fail for
     // incomplete types. Otherwise it just assumes that incomplete types do not
     // have a trace method, which may not be true.
-    static const bool value = sizeof(YesType) + sizeof(T) == sizeof(checkHasTraceMethod<T>(0)) + sizeof(T);
+    static const bool hasTraceMethod = sizeof(YesType) + sizeof(T) == sizeof(checkHasTraceMethod<T>(0)) + sizeof(T);
+    static const bool value = hasTraceMethod || HasTraceNewMethod<T>::value;
 };
 
 // Convenience template wrapping the NeedsTracingLazily template in
 // Collection Traits. It helps make the code more readable.
 template<typename Traits>
 class ShouldBeTraced {
 public:
     static const bool value = Traits::template NeedsTracingLazily<>::value;
 };
 
 template<typename T, typename U>
 struct NeedsTracing<std::pair<T, U> > {
     static const bool value = NeedsTracing<T>::value || NeedsTracing<U>::value || IsWeak<T>::value || IsWeak<U>::value;
 };
 
 } // namespace WTF
 
 #endif // TypeTraits_h