Julia does not build with gcc 5.0 development versions

[nalimilan]

I see this with current release-0.3 branch when building the Fedora package with LLVM 3.5. Looks like we need to backport one or several commits (master builds fine).

gcc -march=x86-64 -m64 -DJL_SYSTEM_IMAGE_PATH="../lib64/julia/sys.ji" -DJULIA_TARGET_ARCH=x86-64 -DSYSTEM_LLVM -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic -std=gnu99 -pipe -fPIC -fno-strict-aliasing -D_FILE_OFFSET_BITS=64 -O3 -ggdb3 -falign-functions -momit-leaf-frame-pointer -I/builddir/build/BUILD/julia/src -I/builddir/build/BUILD/julia/src/support -I/builddir/build/BUILD/julia/build/usr/include -Wall -Wno-strict-aliasing -fno-omit-frame-pointer -c repl.c -o repl.o
g++ -march=x86-64 -m64 -O3 -ggdb3 -falign-functions -momit-leaf-frame-pointer -I/builddir/build/BUILD/julia/src -I/builddir/build/BUILD/julia/src/support -I/builddir/build/BUILD/julia/build/usr/include -Wall -Wno-strict-aliasing -fno-omit-frame-pointer repl.o -o /builddir/build/BUILD/julia/build/usr/bin/julia -L/builddir/build/BUILD/julia/build/usr/lib64/julia -L/builddir/build/BUILD/julia/build/usr/lib64 -L/builddir/build/BUILD/julia/build/usr/lib64 -ljulia -Wl,-Bdynamic -Wl,--no-whole-archive -ldl -lrt -lpthread -Wl,--export-dynamic -Wl,--version-script=/builddir/build/BUILD/julia/src/julia.expmap -Wl,--no-whole-archive -lunwind-generic -lunwind -L/usr/lib64/llvm -lLLVM-3.5.0 -Wl,-rpath,$ORIGIN/../lib64/julia -Wl,-rpath,$ORIGIN/../lib64 -Wl,-z,origin
/builddir/build/BUILD/julia/build/usr/lib64/libjulia.so: undefined reference to `llvm::TargetRegistry::lookupTarget(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&)'
/builddir/build/BUILD/julia/build/usr/lib64/libjulia.so: undefined reference to `llvm::LoopPass::createPrinterPass(llvm::raw_ostream&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) const'
/builddir/build/BUILD/julia/build/usr/lib64/libjulia.so: undefined reference to `llvm::EngineBuilder::selectTarget(llvm::Triple const&, llvm::StringRef, llvm::StringRef, llvm::SmallVectorImpl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > const&)'
/builddir/build/BUILD/julia/build/usr/lib64/libjulia.so: undefined reference to `llvm::raw_fd_ostream::raw_fd_ostream(char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, llvm::sys::fs::OpenFlags)'

https://copr-be.cloud.fedoraproject.org/results/nalimilan/julia-nightlies/fedora-rawhide-x86_64/julia-0.3.6-0.20150212.fc21/build.log

[tkelman]

As mentioned here #10058 (comment) I'm pretty sure this is unique to USE_SYSTEM_LLVM or maybe using LLVM as a shared library.

[tkelman]

I can't reproduce this on Ubuntu 14.04, even using shared-library system LLVM 3.5.0. What's the easiest way to reproduce the copr build environment, Docker container maybe?

[vtjnash]

it's perhaps worth noting that llvm35 is not a supported configuration for release-0.3, and llvm36 support is still a work-in-progress on master (#9336)

[tkelman]

Yes but it appears to be what distributions (Debian, Fedora, probably others) are all using because LLVM 3.3 is no longer available in those repositories.

[nalimilan]

Actually the same error started to appear on master builds today, and I also get it with 0.3.5. I think it may have to do with the introduction of gcc 5.0 in Fedora rawhide. Maybe it's not even related to LLVM 3.5.

A new development version is coming soon, I'll check whether the failure is gone with it. I guess I should file a bug against Fedora/gcc -- except if you think Julia might be doing something wrong that the new gcc merely unveiled.

[nalimilan]

Filed a bug in Fedora, let's see what they say: https://bugzilla.redhat.com/show_bug.cgi?id=1192930

[tkelman]

Oh, right, I missed the __cxx11 at first glance. I bet it's the GCC 5 ABI change (http://developerblog.redhat.com/2015/02/10/gcc-5-in-fedora/), we probably need to build libjulia with -std=c++11 now. I think llvm-config --cxxflags would have included that but llvm-config --cflags does not.

[nalimilan]

I've tried adding -std=c++11 to calls to all g++ calls, doesn't fix the problem:
https://kojipkgs.fedoraproject.org//work/tasks/406/8950406/build.log

But I may well have missed something.

[tkelman]

Hrm, maybe -D_GLIBCXX_USE_CXX11_ABI=0 then? (or =1?) Do we know which way the LLVM 3.5 package was built?

[nalimilan]

I think you nailed it. LLVM was built with gcc 4.9, and on Fedora rawhide (to be F23) -D_GLIBCXX_USE_CXX11_ABI=1 is the default now. So the situation is a temporarily broken since packages have not been rebuilt yet, as the focus is on F22 (to be released this spring). The build works fine on F22 where -D_GLIBCXX_USE_CXX11_ABI=0 is still the default. I'm currently rebuilding LLVM with -D_GLIBCXX_USE_CXX11_ABI=1 to see whether Julia builds fine with it on rawhide. If it works then I guess there's no bug.

[nalimilan]

The LLVM build fails on rawhide, so I cannot check. Let's say it works and leave the LLVM Fedora maintainers sort this out.

Do you think adding -std=c++11 would be good anyway, or should we close this bug?

[tkelman]

We might end up needing it at some point after upgrading to LLVM 3.5, I'm not sure yet.

[nalimilan]

OK, we'll see at that point then.

[nalimilan]

Good news, Julia builds just fine now that LLVM has been rebuilt with -D_GLIBCXX_USE_CXX11_ABI=1. So no changes needed!