diff --git a/reactos/drivers/storage/scsiport/scsiport.spec b/reactos/drivers/storage/scsiport/scsiport.spec
index 7d580bb2a81..65c75471c4d 100644
--- a/reactos/drivers/storage/scsiport/scsiport.spec
+++ b/reactos/drivers/storage/scsiport/scsiport.spec
@@ -1,4 +1,4 @@
-#ifdef _M_AMD64
+#ifdef __x86_64__
 #define MAYBEFWD(x)
 #else
 #define MAYBEFWD(x) x