Fix strict aliasing crash on x64.

Review URL: http://codereview.chromium.org/164498


git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2692 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

SConstruct

@@ -169,7 +169,7 @@ LIBRARY_FLAGS = {
     },
     'arch:x64': {
       'CPPDEFINES':   ['V8_TARGET_ARCH_X64'],
-      'CCFLAGS':      ['-fno-strict-aliasing', '-m64'],
+      'CCFLAGS':      ['-m64'],
       'LINKFLAGS':    ['-m64'],
     },
     'prof:oprofile': {

src/compilation-cache.cc

@@ -290,7 +290,6 @@ void CompilationCacheScript::Put(Handle<String> source,
   HandleScope scope;
   ASSERT(boilerplate->IsBoilerplate());
   Handle<CompilationCacheTable> table = GetTable(0);
-  // TODO(X64): -fstrict-aliasing causes a problem with table.  Fix it.
   CALL_HEAP_FUNCTION_VOID(table->Put(*source, *boilerplate));
 }
 

src/handles-inl.h

@@ -39,7 +39,7 @@ namespace internal {
 template<class T>
 Handle<T>::Handle(T* obj) {
   ASSERT(!obj->IsFailure());
-  location_ = reinterpret_cast<T**>(HandleScope::CreateHandle(obj));
+  location_ = HandleScope::CreateHandle(obj);
 }
 
 

src/handles.h

@@ -82,7 +82,7 @@ class Handle {
   }
 
   static Handle<T> null() { return Handle<T>(); }
-  bool is_null() {return location_ == NULL; }
+  bool is_null() { return location_ == NULL; }
 
   // Closes the given scope, but lets this handle escape. See
   // implementation in api.h.
@@ -119,15 +119,18 @@ class HandleScope {
   static int NumberOfHandles();
 
   // Creates a new handle with the given value.
-  static inline Object** CreateHandle(Object* value) {
-    void** result = current_.next;
-    if (result == current_.limit) result = Extend();
+  template <typename T>
+  static inline T** CreateHandle(T* value) {
+    void** cur = current_.next;
+    if (cur == current_.limit) cur = Extend();
     // Update the current next field, set the value in the created
     // handle, and return the result.
-    ASSERT(result < current_.limit);
-    current_.next = result + 1;
-    *reinterpret_cast<Object**>(result) = value;
-    return reinterpret_cast<Object**>(result);
+    ASSERT(cur < current_.limit);
+    current_.next = cur + 1;
+
+    T** result = reinterpret_cast<T**>(cur);
+    *result = value;
+    return result;
   }
 
  private: