Cxx and 0.7

I’m trying to port some 0.6 code to 1.0 by way of 0.7, and I’m having trouble with the Cxx package.

Yes, I know Cxx is in an intermediate state. But this code is mission critical, so I don’t really have a choice but go forward with it.

My problem:

  • with the Julia 0.7 binary, I get a “JULIA_HOME” not defined error when adding Cxx. This appears to be a known problem. The suggested fix is to build Julia from source.

  • when built from source, the Cxx package adds and builds, but in use it reports that it can’t find random, name-mangled functions in the library I’m trying to call. The suggested fix is to build Julia with Clang.

  • when built from source with Clang, ]build Cxx halts with the following error:

    Error: Error building Cxx:
    │ WARNING: JULIA_HOME environment variable is renamed to JULIA_BINDIR
    │ g++ -D_GLIBCXX_USE_CXX11_ABI=1 -fno-rtti -DLIBRARY_EXPORTS -fPIC -O0 -g -std=c++11 -
    I/home/glen/Code/julia-0.7.0/usr/bin/…/…/src/support -I/home/glen/Code/julia-0.7.0/usr/bin/…/include -I/home/glen/Code/julia-0.7.0/usr/bin/…/…/deps/srccache/llvm-6.0.0/tools/clang/lib -I/home/glen/Code/julia-0.7.0/usr/bin/…/…/deps/llvm-6.0.0/tools/clang/lib -c …/src/bootstrap.cpp -o build/bootstrap.o
    │ Not building debug library because corresponding julia DEBUG library does not exist.
    │ To build, simply run the build again once the library at
    │ /libjulia-debug.so
    │ has been built.
    │ …/src/bootstrap.cpp:55:10: fatal error: clang/Sema/ScopeInfo.h: No such file or directory
    #include “clang/Sema/ScopeInfo.h”
    │ ^~~~~~~~~~~~~~~~~~~~~~~~
    │ compilation terminated.

Suggestions, please. I’m open to anything that will let me get this code working. I’m using a relatively stock Ubuntu 18.04 system. In all cases I’ve checked out the Cxx#master branch via Pkg.

Are you able to switch to using CxxWrap instead? My understanding is that it’s a bit less pleasant to use but more stable and works on 1.0

It’s a bit hard to tell, but the README seems to imply that CxxWrap doesn’t support 0.7.

It would be a lot more work.

I’d love to hear from anyone who has successfully gotten Cxx working with either 0.7 or 1.0…

Here is claimed to get it working.

Interesting. That particular example works for me under 1.0.3 as well. I have not tried running my code under 1.0 because I need it to run under 0.7 first. I built 1.0.3 from source, but not using Clang.

I am now rebuilding 0.7.0 without Clang, to see whether the example works there as well. Updates as they happen.

No joy. I built a fresh Julia 0.7.0 from source, including all the dependencies. I then get:

(v0.7) pkg> add Cxx#master
    Updating git-repo `https://github.com/Keno/Cxx.jl.git`

┌ Warning: project file for Cxx at /tmp/tmp9P4aqW is missing a version entry
└ @ Pkg.Types ~/Code/julia-0.7.0/usr/share/julia/stdlib/v0.7/Pkg/src/Types.jl:700
Resolving package versions…
Updating ~/.julia/environments/v0.7/Project.toml
[a0b5b9ef] + Cxx v0.2.0+ #master (https://github.com/Keno/Cxx.jl.git)
Updating ~/.julia/environments/v0.7/Manifest.toml
[a0b5b9ef] + Cxx v0.2.0+ #master (https://github.com/Keno/Cxx.jl.git)
Building Cxx → ~/.julia/packages/Cxx/81BGP/deps/build.log
┌ Error: Error building Cxx:
│ WARNING: JULIA_HOME environment variable is renamed to JULIA_BINDIR
│ mkdir src
│ curl -Lo src/cfe-6.0.0.src.tar.xz http://releases.llvm.org/6.0.0/cfe-6.0.0.src.tar.xz
│ Not building debug library because corresponding julia DEBUG library does not exist.
│ To build, simply run the build again once the library at
│ /libjulia-debug.so
│ has been built.
│ % Total % Received % Xferd Average Speed Time Time Time Current
│ Dload Upload Total Spent Left Speed
100 5307 0 5307 0 0 80409 0 --:–:-- --:–:-- --:–:-- 80409
│ mkdir -p src/clang-6.0.0
│ tar -C src/clang-6.0.0 --strip-components=1 -xf src/cfe-6.0.0.src.tar.xz
│ xz: (stdin): File format not recognized
│ tar: Child returned status 1
│ tar: Error is not recoverable: exiting now
│ BuildBootstrap.Makefile:103: recipe for target ‘src/clang-6.0.0’ failed
│ make: *** [src/clang-6.0.0] Error 2
│ [ Info: Building julia source build
│ ERROR: LoadError: failed process: Process(make -j12 -f BuildBootstrap.Makefile BASE_JULIA_BIN=/home/glen/Code/julia-0.7.0/usr/bin BASE_JULIA_SRC=/home/glen/Code/julia-0.7.0/usr/bin/../.., ProcessExited(2)) [2]
│ Stacktrace:
│ [1] error(::String, ::Base.Process, ::String, ::Int64, ::String) at ./error.jl:42
│ [2] pipeline_error at ./process.jl:712 [inlined]
│ [3] #run#509(::Bool, ::Function, ::Cmd) at ./process.jl:670
│ [4] run(::Cmd) at ./process.jl:668
│ [5] top-level scope at none:0
│ [6] include at ./boot.jl:317 [inlined]
│ [7] include_relative(::Module, ::String) at ./loading.jl:1038
│ [8] include(::Module, ::String) at ./sysimg.jl:29
│ [9] include(::String) at ./client.jl:398
│ [10] top-level scope at none:0
│ in expression starting at /home/glen/.julia/packages/Cxx/81BGP/deps/build.jl:54
│ writing path.jl file
│ Tuning for julia installation at /home/glen/Code/julia-0.7.0/usr/bin with sources possibly at /home/glen/Code/julia-0.7.0/usr/bin/…/…
└ @ Pkg.Operations ~/Code/julia-0.7.0/usr/share/julia/stdlib/v0.7/Pkg/src/Operations.jl:1068

Julia1.0: Cxx source build Cxx binary build(download and unzip prebuild binaries)
Linux :white_check_mark: master :white_check_mark: comment
maxOS :white_check_mark: PR#400 :white_check_mark: comment
Windows :x: :x:
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CxxWrap 0.7.4 supports Julia 0.7 and 1.0. Later versions only support Julia 1.0.