[PATCH] util.c [PATCH] perlhack.pod (Was: Re: threads crashes inTru64)

I found it - calloc() for zero bytes is nonportable.  It might return
a valid pointer to the heap, or it could return NULL.  In Tru64 and AIX
it returns the latter.  (I actually fixed this same bug in Parrot not
too long ago.)  No, I didn't look at which code tried to allocate zero
bytes, but I think it was eight things each of zero bytes.

Please find attached two patches:

(1) util.c that fortifies Perl_safesyscalloc() against zero allocs
    by always calloc()ing (or malloc()ing) at least something.  I also
    added "wrap-around" guards similar to PERL_MALLOC_WRAP().

(2) adds some notes to perlhack

• threads crashes in Tru64 by Jarkko Hietaniemi
• Re: threads crashes in Tru64 by Jarkko Hietaniemi
• Re: threads crashes in Tru64 by Nicholas Clark
• Re: threads crashes in Tru64 by Philip M. Gollucci
• Re: threads crashes in Tru64 by Jarkko Hietaniemi
• Re: threads crashes in Tru64 by Jarkko Hietaniemi
• [PATCH] util.c [PATCH] perlhack.pod (Was: Re: threads crashes inTru64) by Jarkko Hietaniemi
• Re: [PATCH] util.c [PATCH] perlhack.pod (Was: Re: threads crashesin Tru64) by H.Merijn Brand
• Re: threads crashes in Tru64 by Jarkko Hietaniemi
• Re: threads crashes in Tru64 by Jarkko Hietaniemi