diff --git a/lvm.c b/lvm.c
index 834dd432..6c92567f 100644
--- a/lvm.c
+++ b/lvm.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lvm.c,v 2.61 2006/01/10 12:50:00 roberto Exp roberto $
+** $Id: lvm.c,v 2.62 2006/01/23 19:51:43 roberto Exp roberto $
 ** Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -376,6 +376,7 @@ void luaV_execute (lua_State *L, int nexeccalls) {
   TValue *k;
   const Instruction *pc;
  reentry:  /* entry point */
+  lua_assert(isLua(L->ci));
   pc = L->savedpc;
   cl = &clvalue(L->ci->func)->l;
   base = L->base;