Re: Emacs 22.1 reproducible crash

[Stefan Monnier]

>> Can the result be freed by passing it to `free'?
>> That's a very important part of the spec.

> Yes.  The function `memalign', which is also implemented in gmalloc.c,
> records the original return value of `malloc' in the linear list
> starting from `_aligned_blocks', and `free' looks through it first.

Good.  (I guess the overhead of searching through a linear list shouldn't
be too much problem, although we may end up having many aligned blocks).

Then after installing the above change, we should fix the logic in alloc.c:

   /* Use posix_memalloc if the system has it and we're using the system's
      malloc (because our gmalloc.c routines don't have posix_memalign although
      its memalloc could be used).  */
   #if defined (HAVE_POSIX_MEMALIGN) && defined (SYSTEM_MALLOC)
   #define USE_POSIX_MEMALIGN 1
   #endif


-- Stefan