Use the "enum hack" to fix the SmiTagging constants.

src/compiler/change-lowering.cc

 // Copyright 2014 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/compiler/change-lowering.h"
 #include "src/compiler/machine-operator.h"
 
 #include "src/compiler/js-graph.h"
 
 namespace v8 {
@@ skipping 32 matching lines @@
 
 Node* ChangeLowering::HeapNumberValueIndexConstant() {
   STATIC_ASSERT(HeapNumber::kValueOffset % kPointerSize == 0);
   const int heap_number_value_offset =
       ((HeapNumber::kValueOffset / kPointerSize) * (machine()->is64() ? 8 : 4));
   return jsgraph()->Int32Constant(heap_number_value_offset - kHeapObjectTag);
 }
 
 
 Node* ChangeLowering::SmiMaxValueConstant() {
-  // TODO(turbofan): Work-around for weird GCC 4.6 linker issue:
-  // src/compiler/change-lowering.cc:46: undefined reference to
-  // `v8::internal::SmiTagging<4u>::kSmiValueSize'
-  // src/compiler/change-lowering.cc:46: undefined reference to
-  // `v8::internal::SmiTagging<8u>::kSmiValueSize'
-  STATIC_ASSERT(SmiTagging<4>::kSmiValueSize == 31);
-  STATIC_ASSERT(SmiTagging<8>::kSmiValueSize == 32);
-  const int smi_value_size = machine()->is64() ? 32 : 31;
+  const int smi_value_size =
+      machine()->is32() ? static_cast<int>(SmiTagging<4>::kSmiValueSize)

[Jarin, 2014/09/01 06:20:21]

You might want to define a static method GetSmiValueSize() in SmiTagging<> to
encapsulate of the ugly cast (and possibly get rid of the enum).

[rossberg, 2014/09/01 09:51:48]

+1

+                        : static_cast<int>(SmiTagging<8>::kSmiValueSize);
   return jsgraph()->Int32Constant(
       -(static_cast<int>(0xffffffffu << (smi_value_size - 1)) + 1));
 }
 
 
 Node* ChangeLowering::SmiShiftBitsConstant() {
-  // TODO(turbofan): Work-around for weird GCC 4.6 linker issue:
-  // src/compiler/change-lowering.cc:46: undefined reference to
-  // `v8::internal::SmiTagging<4u>::kSmiShiftSize'
-  // src/compiler/change-lowering.cc:46: undefined reference to
-  // `v8::internal::SmiTagging<8u>::kSmiShiftSize'
-  STATIC_ASSERT(SmiTagging<4>::kSmiShiftSize == 0);
-  STATIC_ASSERT(SmiTagging<8>::kSmiShiftSize == 31);
-  const int smi_shift_size = machine()->is64() ? 31 : 0;
+  const int smi_shift_size =
+      machine()->is32() ? static_cast<int>(SmiTagging<4>::kSmiShiftSize)
+                        : static_cast<int>(SmiTagging<8>::kSmiShiftSize);
   return jsgraph()->Int32Constant(smi_shift_size + kSmiTagSize);
 }
 
 
 Node* ChangeLowering::AllocateHeapNumberWithValue(Node* value, Node* control) {
   // The AllocateHeapNumber() runtime function does not use the context, so we
   // can safely pass in Smi zero here.
   Node* context = jsgraph()->ZeroConstant();
   Node* effect = graph()->NewNode(common()->ValueEffect(1), value);
   const Runtime::Function* function =
@@ skipping 162 matching lines @@
 Graph* ChangeLowering::graph() const { return jsgraph()->graph(); }
 
 
 CommonOperatorBuilder* ChangeLowering::common() const {
   return jsgraph()->common();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8