With --build=powerpc64le-unknown-linux-gnu in the config_opts section of build-farm.conf, the build and the regression were successful.
Well, by the time the decision is made on this, I have enabled only 9.4+ runs on ppc64le. The results from this buildfarm member 'clam' are now being reported.
On Wed, Dec 9, 2015 at 12:05 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
Robert Haas <robertmhaas@gmail.com> writes: > I don't really want to get into an argument about this, but is the > reason we haven't updated config.guess and config.sub in the past that > it presents an actual stability risk, or just that nobody's asked > before? Because the first one is a good reason not to do it now, but > the second one isn't.
Well, I see at least one case in the git history where we explicitly declined to update config.guess/config.sub:
Author: Tom Lane <tgl@sss.pgh.pa.us> Branch: master Release: REL9_3_BR [5c7603c31] 2013-06-04 15:42:02 -0400 Branch: REL9_2_STABLE Release: REL9_2_5 [612ecf311] 2013-06-04 15:42:21 -0400
Add ARM64 (aarch64) support to s_lock.h.
Use the same gcc atomic functions as we do on newer ARM chips. (Basically this is a copy and paste of the __arm__ code block, but omitting the SWPB option since that definitely won't work.)
Back-patch to 9.2. The patch would work further back, but we'd also need to update config.guess/config.sub in older branches to make them build out-of-the-box, and there hasn't been demand for it.
Mark Salter
More generally, I think "does updating config.guess, in itself, pose a stability risk" is a false statement of the issue. The real issue is do we want to start supporting a new platform in 9.1-9.3; that is, IMO if we accept this request then we are buying into doing *whatever is needed* to support ppc64le on those branches. Maybe that will stop with config.guess/config.sub, or maybe it won't.
Setting this precedent will also make it quite hard to reject future requests to back-patch support for other new platforms.
I'm not planning to go to war about this issue either. But I do think there's a slippery-slope hazard here, and we should be prepared for the logical consequences of accepting such a request. Or if we're going to have a policy allowing this request but not every such request, somebody had better enunciate what that policy is.
regards, tom lane
(BTW, so far as direct stability hazards go, I would guess that the key question is how much version skew can be tolerated between autoconf and config.guess/config.sub. I have no idea about that; Peter E. might. But I do note that pre-9.4 branches use an older autoconf version.)