Created attachment 1066731 [details] clang compiled binary Description of problem: Dodji and I were running abidiff against an ELF file compiled by clang and we discovered that at least the version of clang that ships with EPEL has an ABI compliance bug. The bug is that for classes that have a vtable, it is supposed to have 3 destructors. D0,D1, and D2. Clang is failing to emit D1. While GCC makes D1 an alias to D2. According to Jason this is a violation of ABI Version-Release number of selected component (if applicable): 3.4.2 I haven't yet been able to get 3.6.2 to compile. How reproducible: at least sometimes. Steps to Reproduce: 1. run abidiff on the two libraries provided 2. note how it appears that GCC adds the D1 destructor as an alias to the D2 destructor For example: Actual results: [A] 'method SpinLockHolder::~SpinLockHolder(int)' {_ZN14SpinLockHolderD1Ev, aliases _ZN14SpinLockHolderD2Ev} Expected results: The D1 destructor aliases the D2 destructor. Additional info: I believe that this only happens when you don't have a virtual base class just virtual functions
Created attachment 1066732 [details] gcc compiled file
https://mentorembedded.github.io/cxx-abi/abi.html#vtable is the source that Jason cited with regards to the ABI. If 3.6.2 doesn't have this ABI compliance problem then a reasonable solution would be just to rebase EPEL to the latest version of the compiler. Simply trying to recompile the rawhide src.rpm does not appear to work for RHEL6.
clang/LLVM 3.5 and later require C++11 support and the version of gcc that comes with RHEL 6 can't be used, so I think that this will have to be fixed as "won't fix" unless someone is will to create a patch for clang/LLVM 3.4.
What about compiling it with DTS?
devtoolset isn't available for use in EPEL. I've tried once or twice to see if that could be possible, but it never made it anywhere ( https://lists.fedoraproject.org/pipermail/epel-devel/2013-September/008737.html ). The best bet would be to make a COPR because then it's pretty straightforward/simple to use devtoolset. I've been wanting to do that for a while, but just haven't had the time to do it. Hopefully, I can look into it in the not too distant future.
I just noticed that this also impacts constructors as can be seen by: 'method GoogleInitializer::~GoogleInitializer(int)' {_ZN17GoogleInitializerD1Ev, aliases _ZN17GoogleInitializerD2Ev} 'method SpinLockHolder::SpinLockHolder(SpinLock*)' {_ZN14SpinLockHolderC1EP8SpinLock, aliases _ZN14SpinLockHolderC2EP8SpinLock}
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EPEL el6 changed to end-of-life (EOL) status on 2020-11-30. EPEL el6 is no longer maintained, which means that it will not receive any further security or bug fix updates. As a result we are closing this bug. If you can reproduce this bug against a currently maintained version of EPEL please feel free to reopen this bug against that version. If you are unable to reopen this bug, please file a new report against the current release. If you experience problems, please add a comment to this bug. Thank you for reporting this bug and we are sorry it could not be fixed.