#_DrawPicture and the mac heap

[STEVE.M@AppleLink.Apple.COM (Carbon-based, S Mitchell,APD)]

Sub:    #_DrawPicture and the mac heap
 
> From: lynch@aristotle.ils.nwu.edu
> I have reason to believe that if DrawPicture is called when
> the mac heap is too small for the picture to be drawn, the
> various shenanigans that go on
> to move the mac/lisp heap divider cause a crash...
 
The Mac heap can move during the _DrawPicture call, but that
routine shouldn't be allocating any heap memory for drawing.
I always _MoveHHi and _HLock the handle to my picture before the
call (and _HUnlock immediately afterwards). How are you able to
tell the divider (assuming these 2 abut) is being moved if the
Mac crashes before it's done?
 
_Steve
 
[ Note to the MCL team: If it's not too late, please remove all
  shenanigans from MCL 2.0 final before shipping it. Thanks! ]