Teresa Johnson via llvm-dev
2016-Oct-12 13:34 UTC
[llvm-dev] unable to compile llvm with gcc 4.7.4
On Wed, Oct 12, 2016 at 6:26 AM, via llvm-dev <llvm-dev at lists.llvm.org> wrote:> On Wed, Oct 12, 2016 at 10:28:36AM +0200, Antoine Pitrou via llvm-dev > wrote: > > On Tue, 11 Oct 2016 13:46:35 -0700 > > Michael Kuperstein via llvm-dev <llvm-dev at lists.llvm.org> wrote: > > > To the best of my understanding - because we want to be able to > bootstrap > > > clang with the system compiler that ships with various linux and BSD > > > distributions. > > > Windows has no equivalent concept. > > > > To elaborate on this: if you want to produce binaries compatible with > > old Linux systems, it is pretty much necessary to build on such an old > > Linux system, because otherwise you'll get bitten by glibc ABI issues > > (not to mention libstdc++, but at least you can link libstdc++ > > statically). > > Then, on the medium term it would be to see if gcc 4.7.4 (the last C > bootstrap-able c++-ish compiler in one step) is phased out from llvm > support in > favor of gcc 4.8. > > But the short term solution would be to fix current llvm against gcc 4.7.4. > > As I said earlier, with the options detailed earlier in this thread, the > LTO > cache and some tools have some troubles with gcc 4.7.4. >I can send a patch to workaround the gcc 4.7.4 bug hitting the LTO compile. But according to James in an earlier response, there are other places where gcc 4.7 doesn't compile the current clang toolchain. So I'd first like to understand whether we still want to keep gcc 4.7 as a supported version, or move to 4.8 as was suggested. What is the process for making that change? If we stick with 4.7 we should have a bot otherwise it will likely stop working again pretty quickly. Teresa> regards, > > -- > Sylvain > _______________________________________________ > LLVM Developers mailing list > llvm-dev at lists.llvm.org > http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev >-- Teresa Johnson | Software Engineer | tejohnson at google.com | 408-460-2413 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20161012/cd4add9c/attachment.html>
Renato Golin via llvm-dev
2016-Oct-12 15:15 UTC
[llvm-dev] unable to compile llvm with gcc 4.7.4
On 12 October 2016 at 14:34, Teresa Johnson via llvm-dev < llvm-dev at lists.llvm.org> wrote:> So I'd first like to understand whether we still want to keep gcc 4.7 as a > supported version, or move to 4.8 as was suggested. What is the process for > making that change? >Same as usual: propose on the list, and hope that no one has any blocking issues. Going to 4.9 failed because many people had reservations, but IIRC, none of those people had reservations against 4.8.> If we stick with 4.7 we should have a bot otherwise it will likely stop > working again pretty quickly. >Yes, same for Clang. I suggest we also move to Clang 3.4 as the minimum and install a quick bot with that. cheers, --renato -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20161012/1e3c09b2/attachment.html>
On Wed, Oct 12, 2016 at 04:15:44PM +0100, Renato Golin wrote:> On 12 October 2016 at 14:34, Teresa Johnson via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > > > So I'd first like to understand whether we still want to keep gcc 4.7 as a > > supported version, or move to 4.8 as was suggested. What is the process for > > making that change? > > > > Same as usual: propose on the list, and hope that no one has any blocking > issues. Going to 4.9 failed because many people had reservations, but IIRC, > none of those people had reservations against 4.8. > > > > > If we stick with 4.7 we should have a bot otherwise it will likely stop > > working again pretty quickly. > > > > Yes, same for Clang. I suggest we also move to Clang 3.4 as the minimum and > install a quick bot with that.Suggestion is not clear answer. How such a decision taken? Is there a board of people which have to vote to valid the choice of minimal gcc (and clang) version effective? Because, currently, the LTO lib caching code (and certainly more as Teresa Johnson pointed out) should be patched. If gcc 4.7 (last 1-step C boostrap-able c++-ish compiler) is phased out, then, to bootstrap llvm from a C compiler/runtime, gcc(4.7.4) + gcc(version>=4.8) will have to be setup first. -- Sylvain
Teresa Johnson via llvm-dev
2016-Oct-12 22:52 UTC
[llvm-dev] unable to compile llvm with gcc 4.7.4
I went ahead and started up an RFC thread for bumping the min GCC version to 4.8. It seems like moving the minimum Clang version could be proposed separately. Thanks, Teresa On Wed, Oct 12, 2016 at 8:15 AM, Renato Golin <renato.golin at linaro.org> wrote:> On 12 October 2016 at 14:34, Teresa Johnson via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > >> So I'd first like to understand whether we still want to keep gcc 4.7 as >> a supported version, or move to 4.8 as was suggested. What is the process >> for making that change? >> > > Same as usual: propose on the list, and hope that no one has any blocking > issues. Going to 4.9 failed because many people had reservations, but IIRC, > none of those people had reservations against 4.8. > > > >> If we stick with 4.7 we should have a bot otherwise it will likely stop >> working again pretty quickly. >> > > Yes, same for Clang. I suggest we also move to Clang 3.4 as the minimum > and install a quick bot with that. > > cheers, > --renato >-- Teresa Johnson | Software Engineer | tejohnson at google.com | 408-460-2413 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20161012/08d13444/attachment.html>