Re: xnrealloc: How and when to properly use it.

[Keith David Bershatsky]

Thank you, Paul, for reviewing and responding to this particular thread.

Based upon your suggestion, I set w->mc_elts.caches = xnrealloc ... and have 
thus far been unable to crash Emacs -- i.e., your suggestion appears to have 
resolved the issue.  I'll do some additional testing tomorrow and report back.

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> Date: [04-27-2019 18:51:51] <27 Apr 2019 18:51:51 -0700>
> From: Paul Eggert <address@hidden>
> To: Keith David Bershatsky <address@hidden>
> Cc: Emacs Devel <address@hidden>
> Subject: Re: xnrealloc: How and when to properly use it.
> 
> Keith David Bershatsky wrote:
> > On a W32 build of Emacs (built with MinGW_32 and ezwinports downloaded a 
> > few years ago), my usage of xnrealloc (more often than not) causes Emacs to 
> > crash when_not_  running under gdb.
> 
> Try the GDB command 'set disable-randomization off'. Of course this makes
> debugging more ... interesting.
> 
> +              /* Decrease the size of the array to a bare minimum. */
> +              xnrealloc (w->mc_elts.caches, 1, sizeof *w->mc_elts.caches);
> 
> That can't be right; at the very least you need to assign the returned value 
> of xnrealloc back to w->mc_elts.caches.