diff --git a/sys/boot/userboot/libstand/Makefile b/sys/boot/userboot/libstand/Makefile
index 692aa5af30e7..35903fc40864 100644
--- a/sys/boot/userboot/libstand/Makefile
+++ b/sys/boot/userboot/libstand/Makefile
@@ -43,7 +43,7 @@ CFLAGS+=	-msoft-float -D_STANDALONE
 
 # standalone components and stuff we have modified locally
 SRCS+=	gzguts.h zutil.h __main.c assert.c bcd.c bswap.c environment.c getopt.c gets.c \
-	globals.c pager.c printf.c strdup.c strerror.c strtol.c random.c \
+	globals.c pager.c printf.c strdup.c strerror.c strtol.c strtoul.c random.c \
 	sbrk.c twiddle.c zalloc.c zalloc_malloc.c
 
 # private (pruned) versions of libc string functions