From 2c333b66bcbf4278bd5d080a6722aad704160905 Mon Sep 17 00:00:00 2001
From: Michael Forney <mforney@mforney.org>
Date: Wed, 8 May 2019 01:14:57 -0700
Subject: [PATCH] Fail on invalid token

Reading a zero-length TIdnt token causes infinite loops or other failures.
---
 yacc.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/yacc.c b/yacc.c
index 01f054e..8ea5137 100644
--- a/yacc.c
+++ b/yacc.c
@@ -837,6 +837,8 @@ nexttk()
 			die("identifier too long");
 		c = fgetc(fin);
 	}
+	if (p == idnt)
+		die("unknown token");
 	*p = 0;
 	if (strcmp(idnt, "%")==0)
 	if (c=='{')
-- 
2.20.1