[CMake] Problem writing on GPFS.

[P. A. Cheeseman]

     I want to thank Rolf here for his advice because I failed to
do so in an off line reply.

     Shortly after I replied to Rolf's note, I received notification from
IBM that the problem is related to our version of GPFS (4.1.0-2).

     Versions 4.1.0-3 and later apparently do not have the problem.

				Best regards,
				Phil

				P. A. Cheeseman
				aai at purdue.edu
				765.496.8224


> -----Original Message-----
> From: Rolf Eike Beer [mailto:eike at sf-mail.de]
> Sent: Tuesday, February 10, 2015 13:44
> To: cmake at cmake.org; aai at purdue.edu
> Subject: Re: [CMake] Problem writing on GPFS.
> 
> P. A. Cheeseman wrote:
> >      System: RHEL6   (2.6.32-504.8.1.el6.x86_64)
> >      Hardware: Various cluster nodes.
> 
> >      A C code with explicit writev() calls, with a NULL pointer in the
> > first iovec entry, also reproduces the behavior.  When the NULL is
> > part of any entry other than the first, the code runs identically for
> > all storage.
> 
> I would suggest contacting Red Hat. This sounds for me like a bug in the
GPFS
> code, especially since the call succeeds if the (NULL, 0) pair is in a
later pair.
> 
> Other than that, I don't see a reason why g++ should emit such a call.
Should
> probably be reported to the gcc guys. Or maybe this is just something in
your
> libc, so gcc isn't at fault at all. Probably time for the Red Hat guys to
> investigate, too ;)
> 
> Eike
> --