diff --git a/sys/external/bsd/sljit/dist/sljit_src/sljitConfig.h b/sys/external/bsd/sljit/dist/sljit_src/sljitConfig.h
index fa6f7860ba73..d2177cc7ad7b 100644
--- a/sys/external/bsd/sljit/dist/sljit_src/sljitConfig.h
+++ b/sys/external/bsd/sljit/dist/sljit_src/sljitConfig.h
@@ -63,7 +63,7 @@
 #endif
 
 #if defined(_KERNEL) && !defined(SLJIT_CACHE_FLUSH)
-#define SLJIT_CACHE_FLUSH(from, to)
+#error "SLJIT_CACHE_FLUSH must be defined."
 #endif
 
 #if defined(_KERNEL)