[es6] silence access-check failure for well-known symbol properties

src/heap/heap.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HEAP_HEAP_H_
 #define V8_HEAP_HEAP_H_
 
 #include <cmath>
 #include <map>
 
@@ skipping 332 matching lines @@
   V(promise_status_symbol)                  \
   V(promise_value_symbol)                   \
   V(sealed_symbol)                          \
   V(stack_trace_symbol)                     \
   V(string_iterator_iterated_string_symbol) \
   V(string_iterator_next_index_symbol)      \
   V(uninitialized_symbol)
 
 #define PUBLIC_SYMBOL_LIST(V)                               \
   V(has_instance_symbol, Symbol.hasInstance)                \
-  V(is_concat_spreadable_symbol, Symbol.isConcatSpreadable) \
   V(is_regexp_symbol, Symbol.isRegExp)                      \
   V(iterator_symbol, Symbol.iterator)                       \
   V(to_primitive_symbol, Symbol.toPrimitive)                \
   V(to_string_tag_symbol, Symbol.toStringTag)               \
   V(unscopables_symbol, Symbol.unscopables)
 
+// Well-Known Symbols are "Public" symbols, which have a bit set which causes
+// them to produce an undefined value when a load results in a failed access
+// check. Because this behaviour is not specified properly as of yet, it only
+// applies to a subset of spec-defined Well-Known Symbols.
+#define WELL_KNOWN_SYMBOL_LIST(V) \
+  V(is_concat_spreadable_symbol, Symbol.isConcatSpreadable)
+
 // Heap roots that are known to be immortal immovable, for which we can safely
 // skip write barriers. This list is not complete and has omissions.
 #define IMMORTAL_IMMOVABLE_ROOT_LIST(V) \
   V(ByteArrayMap)                       \
   V(BytecodeArrayMap)                   \
   V(FreeSpaceMap)                       \
   V(OnePointerFillerMap)                \
   V(TwoPointerFillerMap)                \
   V(UndefinedValue)                     \
   V(TheHoleValue)                       \
@@ skipping 191 matching lines @@
 #define STRING_INDEX_DECLARATION(name, str) k##name##RootIndex,
         INTERNALIZED_STRING_LIST(STRING_INDEX_DECLARATION)
 #undef STRING_DECLARATION
 
 #define SYMBOL_INDEX_DECLARATION(name) k##name##RootIndex,
             PRIVATE_SYMBOL_LIST(SYMBOL_INDEX_DECLARATION)
 #undef SYMBOL_INDEX_DECLARATION
 
 #define SYMBOL_INDEX_DECLARATION(name, description) k##name##RootIndex,
                 PUBLIC_SYMBOL_LIST(SYMBOL_INDEX_DECLARATION)
+                    WELL_KNOWN_SYMBOL_LIST(SYMBOL_INDEX_DECLARATION)
 #undef SYMBOL_INDEX_DECLARATION
 
 // Utility type maps
 #define DECLARE_STRUCT_MAP(NAME, Name, name) k##Name##MapRootIndex,
-                    STRUCT_LIST(DECLARE_STRUCT_MAP)
+                        STRUCT_LIST(DECLARE_STRUCT_MAP)
 #undef DECLARE_STRUCT_MAP
-                        kStringTableRootIndex,
+                            kStringTableRootIndex,
 
 #define ROOT_INDEX_DECLARATION(type, name, camel_name) k##camel_name##RootIndex,
     SMI_ROOT_LIST(ROOT_INDEX_DECLARATION)
 #undef ROOT_INDEX_DECLARATION
         kRootListLength,
     kStrongRootListLength = kStringTableRootIndex,
     kSmiRootsStart = kStringTableRootIndex + 1
   };
 
   // Indicates whether live bytes adjustment is triggered
@@ skipping 533 matching lines @@
 #define STRING_ACCESSOR(name, str) inline String* name();
   INTERNALIZED_STRING_LIST(STRING_ACCESSOR)
 #undef STRING_ACCESSOR
 
 #define SYMBOL_ACCESSOR(name) inline Symbol* name();
   PRIVATE_SYMBOL_LIST(SYMBOL_ACCESSOR)
 #undef SYMBOL_ACCESSOR
 
 #define SYMBOL_ACCESSOR(name, description) inline Symbol* name();
   PUBLIC_SYMBOL_LIST(SYMBOL_ACCESSOR)
+  WELL_KNOWN_SYMBOL_LIST(SYMBOL_ACCESSOR)
 #undef SYMBOL_ACCESSOR
 
   Object* root(RootListIndex index) { return roots_[index]; }
   Handle<Object> root_handle(RootListIndex index) {
     return Handle<Object>(&roots_[index]);
   }
 
   // Generated code can embed this address to get access to the roots.
   Object** roots_array_start() { return roots_; }
 
@@ skipping 1579 matching lines @@
   DisallowHeapAllocation no_allocation;  // i.e. no gc allowed.
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer);
 };
 #endif  // DEBUG
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_HEAP_H_