1--- a/src/lparser.c
2+++ b/src/lparser.c
3@@ -301,6 +301,7 @@
4 expdesc key;
5 singlevaraux(fs, ls->envn, var, 1); /* get environment variable */
6 lua_assert(var->k == VLOCAL || var->k == VUPVAL);
7+ luaK_exp2anyregup(fs, var); /* but could be a constant */
8 codestring(ls, &key, varname); /* key is variable name */
9 luaK_indexed(fs, var, &key); /* env[varname] */
10 }