diff --git a/reactos/lib/sdk/crt/precomp.h b/reactos/lib/sdk/crt/precomp.h
index c60b2f83eb2..847d76b2e05 100644
--- a/reactos/lib/sdk/crt/precomp.h
+++ b/reactos/lib/sdk/crt/precomp.h
@@ -44,6 +44,7 @@
 WINE_DEFAULT_DEBUG_CHANNEL(msvcrt);
 #endif
 #else
+#define NDEBUG
 #include <debug.h>
 #define TRACE DPRINT
 #define WARN DPRINT1