Joseba García Echebarria      2010-12-15 01:55:22 PST

I believe the crash is caused by a check not being performed on wether an
SDL_Touch element is NULL before using it in the SDL_SendTouchMotion function
in src/events/SDL_touch.c around line 400.
Judging from the rest of the code, there's a missing

    if (!touch) {
        return 0;
    }

before using "touch" as SDL_GetFinger(), SDL_GetFingerIndexId() use
touch->num_fingers without checking.

I can attach a patch if you like. It seems pretty straightforward, though.

I have yet to discover why touch is being returned as NULL as this error is
only triggered when an actual gesture has been performed, maybe something
related to SDL_AddTouch()?