Reland: Introduce a V8_NORETURN macro and use it to make GCC 4.9.2 happy again.

test/cctest/test-atomicops.cc

 // Copyright 2014 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 139 matching lines @@
 
   value = k_test_val;
   new_value = NoBarrier_AtomicExchange(&value, 5);
   CHECK_EQU(5, value);
   CHECK_EQU(k_test_val, new_value);
 }
 
 
 template <class AtomicType>
 static void TestAtomicIncrementBounds() {
-  // Test at rollover boundary between int_max and int_min.
-  AtomicType test_val =
-      static_cast<AtomicType>(1) << (NUM_BITS(AtomicType) - 1);
-  AtomicType value = -1 ^ test_val;
+  // Test at 32-bit boundary for 64-bit atomic type.
+  AtomicType test_val = static_cast<AtomicType>(1)
+                        << (NUM_BITS(AtomicType) / 2);
+  AtomicType value = test_val - 1;
   AtomicType new_value = NoBarrier_AtomicIncrement(&value, 1);
   CHECK_EQU(test_val, value);
   CHECK_EQU(value, new_value);
 
-  NoBarrier_AtomicIncrement(&value, -1);
-  CHECK_EQU(-1 ^ test_val, value);
-
-  // Test at 32-bit boundary for 64-bit atomic type.
-  test_val = static_cast<AtomicType>(1) << (NUM_BITS(AtomicType) / 2);
-  value = test_val - 1;
-  new_value = NoBarrier_AtomicIncrement(&value, 1);
-  CHECK_EQU(test_val, value);
-  CHECK_EQU(value, new_value);
-
   NoBarrier_AtomicIncrement(&value, -1);
   CHECK_EQU(test_val - 1, value);
 }
 
 
 // Return an AtomicType with the value 0xa5a5a5..
 template <class AtomicType>
 static AtomicType TestFillValue() {
   AtomicType val = 0;
   memset(&val, 0xa5, sizeof(AtomicType));
@@ skipping 112 matching lines @@
   TestStore<Atomic32>();
   TestStore<AtomicWord>();
 }
 
 
 TEST(Load) {
   TestLoadAtomic8();
   TestLoad<Atomic32>();
   TestLoad<AtomicWord>();
 }