diff --git a/reactos/ntoskrnl/include/internal/debug.h b/reactos/ntoskrnl/include/internal/debug.h
index b71412b04d9..148da1b3005 100644
--- a/reactos/ntoskrnl/include/internal/debug.h
+++ b/reactos/ntoskrnl/include/internal/debug.h
@@ -52,6 +52,7 @@
 
 #define CPRINT(args...)
 #define assert(x)
+#define assertmsg(_c_, _m_)
 
 #endif /* DBG */