define ATOMICOPS_COMPILER_BARRIER in platform.h

src/platform-cygwin.cc

 // 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 61 matching lines @@
 
 
 int OS::ActivationFrameAlignment() {
   // With gcc 4.4 the tree vectorization optimizer can generate code
   // that requires 16 byte alignment such as movdqa on x86.
   return 16;
 }
 
 
 void OS::ReleaseStore(volatile AtomicWord* ptr, AtomicWord value) {
-  __asm__ __volatile__("" : : : "memory");
+  ATOMICOPS_COMPILER_BARRIER();
   // An x86 store acts as a release barrier.
   *ptr = value;
 }
 
 const char* OS::LocalTimezone(double time) {
   if (isnan(time)) return "";
   time_t tv = static_cast<time_t>(floor(time/msPerSecond));
   struct tm* t = localtime(&tv);
   if (NULL == t) return "";
   return tzname[0];  // The location of the timezone string on Cygwin.
@@ skipping 683 matching lines @@
 
 
 void Sampler::Stop() {
   ASSERT(IsActive());
   SamplerThread::RemoveActiveSampler(this);
   SetActive(false);
 }
 
 
 } }  // namespace v8::internal