lua

commit aaf35336533c17cbeb9ac8137d13cd7908a13327
parent b529aefc531276775f8827052d5594749232cf07
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date:   Wed, 12 Jun 2024 16:03:58 -0300

Tricky _PROMPT may trigger undefined behavior in lua.c

Diffstat:
M
lua.c
 | 
5
+++--

1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/lua.c b/lua.c
@@ -115,12 +115,13 @@ static void l_message (const char *pname, const char *msg) {
 
 /*
 ** Check whether 'status' is not OK and, if so, prints the error
-** message on the top of the stack. It assumes that the error object
-** is a string, as it was either generated by Lua or by 'msghandler'.
+** message on the top of the stack.
 */
 static int report (lua_State *L, int status) {
   if (status != LUA_OK) {
     const char *msg = lua_tostring(L, -1);
+    if (msg == NULL)
+      msg = "(error message not a string)";
     l_message(progname, msg);
     lua_pop(L, 1);  /* remove message */
   }