On 08/25/2013 02:16 PM, Kinkie wrote: > how about only enabling it on 32-bit builds and testing it out? > If Large Rock needs it, then removing it altoghether is not a viable option.
To test out 64-bit atomics I was talking about, you may try to build the Collapsed Forwarding branch on lp: https://code.launchpad.net/~measurement-factory/squid/collapsed-fwd Building current trunk code would not test that aspect because the current code does not use 64-bit atomics AFAIK. IIRC, they were removed some time ago to avoid exactly these problems (it was possible to avoid them by using smaller atomics back then). HTH, Alex. > On Sun, Aug 25, 2013 at 10:04 PM, Alex Rousskov > <rouss...@measurement-factory.com> wrote: >> On 08/25/2013 01:08 PM, Kinkie wrote: >> >>> I've traced down at least some build failures to our use of -march=native. >>> What apparently happens is that in some ocasions gcc emits some mmx >>> instructions which fail with a SIGILL. >>> >>> We have a few choices: >>> 1- leave the builds broken for now and try rework the code >>> 2- add an --enable-extra-compiler-optimizations configure switch to >>> optionally enable -march=native instead of unconditionally. >>> 3- work around this on the broken nodes and on those only by using >>> build trickery. >>> >>> Thoughts? >>> I'd favor option 2'; we can then leave a specifically-broken build job >>> so that when some change we make helps fix the build, we will know. >> >> IIRC, -march=native or similar was needed to build Squid on some 32-bit >> systems. Without it, the build (linking) failed due to the lack of >> 64-bit atomic operations if compiler assumes it needs to preserve >> compatibility with much older 32 bit systems. >> >> Current trunk does not use such operations, but the pending Large Rock >> and Collapsed Forward code do (because swap_file_sz that they need to >> keep in sync across Squid kids is 64 bits). >> >> I hope this info helps you make the right decision but I do not know >> enough about the related compiler options to pick the right choice among >> the three offered. >> >> >> Thank you, >> >> Alex. >> > > >
