diff --git a/opal/mca/pmix/pmix2x/pmix/src/atomics/sys/sync_builtin/atomic.h b/opal/mca/pmix/pmix2x/pmix/src/atomics/sys/sync_builtin/atomic.h
index 51a9a1409b..8823a7d46c 100644
--- a/opal/mca/pmix/pmix2x/pmix/src/atomics/sys/sync_builtin/atomic.h
+++ b/opal/mca/pmix/pmix2x/pmix/src/atomics/sys/sync_builtin/atomic.h
@@ -46,7 +46,7 @@ static inline void pmix_atomic_wmb(void)
     __sync_synchronize();
 }
 
-#define MB() pmix_atomic_mb()
+#define PMIXMB() pmix_atomic_mb()
 
 /**********************************************************************
  *