Kern Handa via llvm-dev
2018-Sep-27 07:46 UTC
[llvm-dev] Ubuntu LLVM packages incompatible with clang built projects?
Hi folks, Not sure if this is the right mailing list target, but I'm trying out the new LLVM 7.0 packages found at http://apt.llvm.org by porting over an existing LLVM 6.0 project of ours to the new version. In doing so, I found that the executable always segfaulted at the same spot with no explanation: 0x0000000000fefe33 in llvm::RegisterTargetMachine<llvm::X86TargetMachine>::Allocator(llvm::Target const&, llvm::Triple const&, llvm::StringRef, llvm::StringRef, llvm::TargetOptions const&, llvm::Optional<llvm::R eloc::Model>, llvm::Optional<llvm::CodeModel::Model>, llvm::CodeGenOpt::Level, bool) () This happens if I build my project and link it against LLVM 7.0 with either clang++ 6.1 or clang++ 7.0. This does not happen if I build my project with g++ 8. I have also confirmed that building LLVM 7.0 with clang++ and then using that private build of the libraries fixes the issue. To summarize, it seems that there's an ABI incompatibility introduced somewhere, which means LLVM 7.0 compiled with gcc can only be used by other projects also built with gcc. Is this something that's being investigated and to be resolved as a fix in 7.1? If not, is there any official release note that's remarking on this incompatibility? Thanks, Kern -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20180927/96df4af4/attachment.html>
Alastair Murray via llvm-dev
2018-Sep-28 15:48 UTC
[llvm-dev] Ubuntu LLVM packages incompatible with clang built projects?
Hi Kern, We also had issues with mixing GCC/Clang builds when testing the 7.0 release branch. My colleague submitted a patch that fixed the issue for us: * https://reviews.llvm.org/D50710 I no longer have a copy of the error we were seeing to see if it was the same, but the fix is to llvm::OptionalStorage and your error message involves llvm::Optional. The patch removes a GCC specific ifdef, and hopefully fixes the issue that made that necessary in the first place, but we never really knew how the GCC miscompilation was expressed. It would be interesting to know whether this resolves your issue, but regardless we should give the patch a prod. Regards, Alastair Murray. On 27/09/18 08:46, Kern Handa via llvm-dev wrote:> Hi folks, > > Not sure if this is the right mailing list target, but I'm trying out > the new LLVM 7.0 packages found at http://apt.llvm.org by porting over > an existing LLVM 6.0 project of ours to the new version. In doing so, > I found that the executable always segfaulted at the same spot with no > explanation: > > 0x0000000000fefe33 in > llvm::RegisterTargetMachine<llvm::X86TargetMachine>::Allocator(llvm::Target > const&, llvm::Triple const&, llvm::StringRef, llvm::StringRef, > llvm::TargetOptions const&, llvm::Optional<llvm::R > eloc::Model>, llvm::Optional<llvm::CodeModel::Model>, > llvm::CodeGenOpt::Level, bool) () > > This happens if I build my project and link it against LLVM 7.0 with > either clang++ 6.1 or clang++ 7.0. This does not happen if I build my > project with g++ 8. > > I have also confirmed that building LLVM 7.0 with clang++ and then > using that private build of the libraries fixes the issue. > > To summarize, it seems that there's an ABI incompatibility introduced > somewhere, which means LLVM 7.0 compiled with gcc can only be used by > other projects also built with gcc. Is this something that's being > investigated and to be resolved as a fix in 7.1? If not, is there any > official release note that's remarking on this incompatibility? > > Thanks, > Kern > > > _______________________________________________ > LLVM Developers mailing list > llvm-dev at lists.llvm.org > http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev-- Alastair Murray Principal Software Engineer, Compilers Codeplay Software Ltd Level C, Argyle House, 3 Lady Lawson St., Edinburgh, EH3 9DR Tel: 0131 466 0503 Fax: 0131 557 6600 Website: http://www.codeplay.com Twitter: https://twitter.com/codeplaysoft This email and any attachments may contain confidential and /or privileged information and is for use by the addressee only. If you are not the intended recipient, please notify Codeplay Software Ltd immediately and delete the message from your computer. You may not copy or forward it, or use or disclose its contents to any other person. Any views or other information in this message which do not relate to our business are not authorized by Codeplay software Ltd, nor does this message form part of any contract unless so stated. As internet communications are capable of data corruption Codeplay Software Ltd does not accept any responsibility for any changes made to this message after it was sent. Please note that Codeplay Software Ltd does not accept any liability or responsibility for viruses and it is your responsibility to scan any attachments. Company registered in England and Wales, number: 04567874 Registered office: Regent House, 316 Beulah Hill, London, United Kingdom, SE19 3HF -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20180928/2a241977/attachment.html>
Reid Kleckner via llvm-dev
2018-Sep-28 16:07 UTC
[llvm-dev] Ubuntu LLVM packages incompatible with clang built projects?
Just be aware that those ifdefs were recommitted and reverted several times, so I'm not sure what the state is. On Fri, Sep 28, 2018 at 8:48 AM Alastair Murray via llvm-dev < llvm-dev at lists.llvm.org> wrote:> Hi Kern, > > We also had issues with mixing GCC/Clang builds when testing the 7.0 > release branch. > > My colleague submitted a patch that fixed the issue for us: > * https://reviews.llvm.org/D50710 > > I no longer have a copy of the error we were seeing to see if it was the > same, but the fix is to llvm::OptionalStorage and your error message > involves llvm::Optional. The patch removes a GCC specific ifdef, and > hopefully fixes the issue that made that necessary in the first place, but > we never really knew how the GCC miscompilation was expressed. > > It would be interesting to know whether this resolves your issue, but > regardless we should give the patch a prod. > > Regards, > Alastair Murray. > > On 27/09/18 08:46, Kern Handa via llvm-dev wrote: > > Hi folks, > > Not sure if this is the right mailing list target, but I'm trying out the > new LLVM 7.0 packages found at http://apt.llvm.org by porting over an > existing LLVM 6.0 project of ours to the new version. In doing so, I found > that the executable always segfaulted at the same spot with no explanation: > > 0x0000000000fefe33 in > llvm::RegisterTargetMachine<llvm::X86TargetMachine>::Allocator(llvm::Target > const&, llvm::Triple const&, llvm::StringRef, llvm::StringRef, > llvm::TargetOptions const&, llvm::Optional<llvm::R > eloc::Model>, llvm::Optional<llvm::CodeModel::Model>, > llvm::CodeGenOpt::Level, bool) () > > This happens if I build my project and link it against LLVM 7.0 with > either clang++ 6.1 or clang++ 7.0. This does not happen if I build my > project with g++ 8. > > I have also confirmed that building LLVM 7.0 with clang++ and then using > that private build of the libraries fixes the issue. > > To summarize, it seems that there's an ABI incompatibility introduced > somewhere, which means LLVM 7.0 compiled with gcc can only be used by other > projects also built with gcc. Is this something that's being investigated > and to be resolved as a fix in 7.1? If not, is there any official release > note that's remarking on this incompatibility? > > Thanks, > Kern > > > _______________________________________________ > LLVM Developers mailing listllvm-dev at lists.llvm.orghttp://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev > > > -- > Alastair Murray > Principal Software Engineer, Compilers > Codeplay Software Ltd > Level C, Argyle House, 3 Lady Lawson St., Edinburgh, EH3 9DR > Tel: 0131 466 0503 > Fax: 0131 557 6600 > Website: http://www.codeplay.com > Twitter: https://twitter.com/codeplaysoft > > This email and any attachments may contain confidential and /or privileged information and > is for use by the addressee only. If you are not the intended recipient, please notify > Codeplay Software Ltd immediately and delete the message from your computer. You may not > copy or forward it, or use or disclose its contents to any other person. Any views or other > information in this message which do not relate to our business are not authorized by > Codeplay software Ltd, nor does this message form part of any contract unless so stated. > As internet communications are capable of data corruption Codeplay Software Ltd does not > accept any responsibility for any changes made to this message after it was sent. Please > note that Codeplay Software Ltd does not accept any liability or responsibility for viruses > and it is your responsibility to scan any attachments. > Company registered in England and Wales, number: 04567874 > Registered office: Regent House, 316 Beulah Hill, London, United Kingdom, SE19 3HF > > _______________________________________________ > LLVM Developers mailing list > llvm-dev at lists.llvm.org > http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev >-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20180928/ee350959/attachment-0001.html>