memory allocation debuging in raine...

[Tux]

In the old days (!), I used something very convenient for that, electric fence, it just created a crash as soon as a read or write was done outside a normal area, then you just used a debuger to find what line triggered this exactly.

But the problem is that multi threaded programs are not supported by electric fence and these days everything is multi threaded (quite normal with all the cores in the cpus now). And so I was left with sub optimal ways to try to debug memory stuff in raine for years.

I tried some, like memwatch which can have its uses, but doesn't track everything so it's a lot less useful than what I had before. Then with clang came -fsanitize=address, a compiler command line argument, which is now handled by gcc too. And this thing works amazingly well ! Most of the asm code is even supported (except the 68020 stuff mostly). I should probably have spent more time playing with this when I added clang support, but I had a lot of stuff to finish at the time. Anyway I finally tried this thoroughly and it produced quite a few fixes in git already :
 - for the okim6295, this stuff is very old but there was a clear buffer overflow for old_bank, I suppose since it was a small array it had some limited effect and didn't create any crash but it could have. That's the most serious one i got so far.
 - all the others are mostly read overflows and since it didn't crash it had no effect, but it's better to have them fixed anyway.

These fixes are in git, and they replace memwatch in debug builds for now.