diff --git a/lib/libufs/Makefile b/lib/libufs/Makefile
index 04195ebb3e5a..fd38b171bafc 100644
--- a/lib/libufs/Makefile
+++ b/lib/libufs/Makefile
@@ -5,7 +5,7 @@ SRCS=	block.c inode.c sblock.c type.c
 INCS=	libufs.h
 NOMAN=	noman
 CFLAGS+= -I${.CURDIR} -D_LIBUFS
-.if defined(DEBUG)
+.if defined(LIBUFS_DEBUG)
 CFLAGS+= -D_LIBUFS_DEBUGGING
 .endif