Fix -fno-common build failure. Taken from https://github.com/awesomeWM/awesome/commit/d256d9055095f27a33696e0aeda4ee20ed4fb1a0 Index: objects/client.h --- objects/client.h.orig +++ objects/client.h @@ -192,7 +192,7 @@ struct client_t ARRAY_FUNCS(client_t *, client, DO_NOTHING) /** Client class */ -lua_class_t client_class; +extern lua_class_t client_class; LUA_OBJECT_FUNCS(client_class, client_t, client)