#get/#set have 'volatile' semantics when compiled with MS Visual C++

Author: alexdowad

ext/atomic_reference.c

@@ -39,6 +39,8 @@ static VALUE ir_initialize(int argc, VALUE* argv, VALUE self) {
 static VALUE ir_get(VALUE self) {
 #if HAVE_GCC_SYNC
     __sync_synchronize();
+#elif defined _MSC_VER
+    MemoryBarrier();
 #endif
     return (VALUE) DATA_PTR(self);
 }
@@ -47,6 +49,8 @@ static VALUE ir_set(VALUE self, VALUE new_value) {
     DATA_PTR(self) = (void *) new_value;
 #if HAVE_GCC_SYNC
     __sync_synchronize();
+#elif defined _MSC_VER
+    MemoryBarrier();
 #endif
     return new_value;
 }