From Lua 5.2: Add debug.upvalueid() and debug.upvaluejoin().

Ditto for lua_upvalueid() and lua_upvaluejoin().

src/lua.h

@@ -336,12 +336,15 @@ LUA_API const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n);
 LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n);
 LUA_API const char *lua_getupvalue (lua_State *L, int funcindex, int n);
 LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n);
-
 LUA_API int lua_sethook (lua_State *L, lua_Hook func, int mask, int count);
 LUA_API lua_Hook lua_gethook (lua_State *L);
 LUA_API int lua_gethookmask (lua_State *L);
 LUA_API int lua_gethookcount (lua_State *L);
 
+/* From Lua 5.2. */
+LUA_API void *lua_upvalueid (lua_State *L, int idx, int n);
+LUA_API void lua_upvaluejoin (lua_State *L, int idx1, int n1, int idx2, int n2);
+
 
 struct lua_Debug {
   int event;