Make sure that names of temporaries do not clash with real variables.

src/heap.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 158 matching lines @@
   V(Arguments_symbol, "Arguments")                                       \
   V(call_symbol, "call")                                                 \
   V(apply_symbol, "apply")                                               \
   V(caller_symbol, "caller")                                             \
   V(boolean_symbol, "boolean")                                           \
   V(Boolean_symbol, "Boolean")                                           \
   V(callee_symbol, "callee")                                             \
   V(constructor_symbol, "constructor")                                   \
   V(code_symbol, ".code")                                                \
   V(result_symbol, ".result")                                            \
+  V(dot_for_symbol, ".for.")                                             \
   V(catch_var_symbol, ".catch-var")                                      \
   V(empty_symbol, "")                                                    \
   V(eval_symbol, "eval")                                                 \
   V(function_symbol, "function")                                         \
   V(length_symbol, "length")                                             \
   V(module_symbol, "module")                                             \
   V(name_symbol, "name")                                                 \
   V(native_symbol, "native")                                             \
   V(null_symbol, "null")                                                 \
   V(number_symbol, "number")                                             \
@@ skipping 2604 matching lines @@
   AssertNoAllocation no_alloc;  // i.e. no gc allowed.
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer);
 };
 #endif  // DEBUG || LIVE_OBJECT_LIST
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_H_