[A5.1 SVN] crash when ending application

no-reply@allegro.cc (tobing) — Wed, 03 Aug 2011 23:07:05 +0000

Since lately, my game crashes during exit. I've tracked down this to

static void shutdown_system_driver(void)

in system.c, where a destructor call for user_exe_path is called, on already destroyed data. It helps to move the new lines up, like this:

#SelectExpand
  1static void shutdown_system_driver(void)
  2{
 if (active_sysdrv) {
    ALLEGRO_CONFIG *temp = active_sysdrv->config;
    if (active_sysdrv->user_exe_path)                   <<-- new lines
       al_destroy_path(active_sysdrv->user_exe_path);   <<-- must be called before shutdown_system()
    if (active_sysdrv->vt && active_sysdrv->vt->shutdown_system)
       active_sysdrv->vt->shutdown_system();
    active_sysdrv = NULL;
    /* active_sysdrv is not accessible here so we copied it */
    al_destroy_config(temp);

    while (!_al_vector_is_empty(&_al_system_interfaces))
       _al_vector_delete_at(&_al_system_interfaces, _al_vector_size(&_al_system_interfaces)-1);
    _al_vector_free(&_al_system_interfaces);
    _al_vector_init(&_al_system_interfaces, sizeof(ALLEGRO_SYSTEM_INTERFACE *));
 }
 18}

no-reply@allegro.cc (Trent Gamblin) — Wed, 03 Aug 2011 23:14:33 +0000

Makes sense, but it's not destroying it twice, it's trying to access user_exe_path through a freed pointer.

no-reply@allegro.cc (kazzmir) — Wed, 03 Aug 2011 23:20:19 +0000

It doesn't look like the user_exe_path has anything to do with with current driver. Can you explain why your fix is necessary?

no-reply@allegro.cc (Trent Gamblin) — Thu, 04 Aug 2011 00:44:54 +0000

My understanding was that active_sysdrv was being freed.

Edit: that comment seems to be erroneuous now.

no-reply@allegro.cc (Elias) — Thu, 04 Aug 2011 01:41:09 +0000

Thanks, I committed it to SVN. (Was also me who had added those 2 lines to the wrong place... just wanted to get my speedhack entry working under Windows and wasn't careful enough )