diff --git a/src/include/storage/s_lock.h b/src/include/storage/s_lock.h
index d6df03f770c..ff7453b9cbd 100644
--- a/src/include/storage/s_lock.h
+++ b/src/include/storage/s_lock.h
@@ -372,7 +372,7 @@ tas(volatile slock_t *lock)
  * requires a barrier.
  */
 #define S_UNLOCK(lock)		(*((volatile slock_t *) (lock)) = 0)
-#elif  __sparcv8
+#elif defined(__sparcv8)
 /* stbar is available (and required for both PSO, RMO), membar isn't */
 #define S_UNLOCK(lock)	\
 do \