harmony-scoping: make assignment to 'const' a late error.

src/arm64/full-codegen-arm64.cc

 // Copyright 2013 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.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
@@ skipping 2355 matching lines @@
       // mode.
       DCHECK(var->IsStackAllocated() || var->IsContextSlot());
       MemOperand location = VarOperand(var, x1);
       if (FLAG_debug_code && op == Token::INIT_LET) {
         __ Ldr(x10, location);
         __ CompareRoot(x10, Heap::kTheHoleValueRootIndex);
         __ Check(eq, kLetBindingReInitialization);
       }
       EmitStoreToStackLocalOrContextSlot(var, location);
     }
+  } else if (IsSignallingAssignmentToConst(var, op, strict_mode())) {
+    __ CallRuntime(Runtime::kThrowConstAssignError, 0);
   }
-  // Non-initializing assignments to consts are ignored.
 }
 
 
 void FullCodeGenerator::EmitNamedPropertyAssignment(Assignment* expr) {
   ASM_LOCATION("FullCodeGenerator::EmitNamedPropertyAssignment");
   // Assignment to a property, using a named store IC.
   Property* prop = expr->target()->AsProperty();
   DCHECK(prop != NULL);
   DCHECK(prop->key()->IsLiteral());
 
@@ skipping 2890 matching lines @@
   return previous_;
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM64