diff --git a/re.c b/re.c
index 9c1905a6..05dca7c5 100644
--- a/re.c
+++ b/re.c
@@ -258,10 +258,10 @@ make_regexp(const char *s, size_t len, bool ignorecase, bool dfa, bool canfatal)
 		refree(rp);
 		if (! canfatal) {
 			/* rerr already gettextized inside regex routines */
-			error("%s: /%.*s/", rerr, (int) len, s);
+			error("%s: /%.*s/", rerr, (int) strlen(s), s);
  			return NULL;
 		}
-		fatal("invalid regexp: %s: /%.*s/", rerr, (int) len, s);
+		fatal("invalid regexp: %s: /%.*s/", rerr, (int) strlen(s), s);
 	}
 
 	/* gack. this must be done *after* re_compile_pattern */