diff --git a/usr.bin/look/look.c b/usr.bin/look/look.c
index 59a9c44c5308..7460a22a8337 100644
--- a/usr.bin/look/look.c
+++ b/usr.bin/look/look.c
@@ -134,7 +134,7 @@ main(int argc, char **argv)
 	do {
 		if ((fd = open(file, O_RDONLY, 0)) < 0 || fstat(fd, &sb))
 			err(2, "%s", file);
-		if (sb.st_size > (off_t)SIZE_T_MAX)
+		if ((size_t)sb.st_size > SIZE_T_MAX)
 			errx(2, "%s: %s", file, strerror(EFBIG));
 		if ((front = mmap(NULL, (size_t)sb.st_size, PROT_READ, MAP_SHARED, fd, (off_t)0)) == MAP_FAILED)
 			err(2, "%s", file);