I tried to email Arnaud Carré about this at his freesurf.fr address, but I got a mail bounce. So, I'll try again, and maybe he'll get it here
I've been using SainT to play (amongst a few other things) Robotz (http://www.atarimania.com/game-atari-st ... 10420.html
), a PD game I remembered playing as a boy, quite a long time ago now.
I noticed a problem while playing it with SainT: if you're using cursor key joystick emulation, you can make impossible joystick movements, which causes problems with Robotz. if you press Up and Down at the same time, the player sprite messes up; and if you press Left and Right simultaneously, the game crashes.
(The debugger didn't seem to stop at the exception, so I didn't try to dig any deeper. I was never much good at figuring out other people's assembly language code anyway.)
Obviously this game has some dodgy coding! - but I bet it won't be the only one. At least by default I suppose SainT should just not report impossible joystick movements? I guess by being consistent (e.g., pressing Left+Right always results in Left), or by preferring whichever direction was pressed most recently, or maybe something else.
(Hatari doesn't suffer from this problem, but it doesn't do a great job of untangling the keypresses. So if you press Left+Right while playing Robotz in Hatari, the guy just stops moving, and he's stuck until you lift off both keys.)