Automatic clang compilation fails

[farao]

Hi,

I want to use infer on (fedora) linux and thus the only available options seems to be building from source. Unfortunately, building from source apparently means that clang must be compiled as well.

1. When I choose this option, and wait a long time for clang to compile, linking of clang fails with a lot of error like this:

• /usr/bin/ld: ../../lib/libLLVMAArch64CodeGen.a(AArch64TargetTransformInfo.cpp.o): relocation R_X86_64_32S against `.rodata' can not be used when making a shared object; recompile with -fPIC
• /usr/bin/ld: ../../lib/libLLVMAArch64CodeGen.a(AArch64SIMDInstrOpt.cpp.o): relocation R_X86_64_32S against `.text' can not be used when making a shared object; recompile with -fPIC
• ...
  Why is this failing?

2. The clang version that is being compiled is the same as the clang on my system (6.0) - can I just tell the infer installation routine to use the system clang?

Thanks,
Marius

[jvillard]

1. Looks similar to build_infer.sh failed on Ubuntu 18.04 #942. Can you try NO_CMAKE_STRIP=1 ./build-infer.sh?
2. I think it's possibly but would be non-trivial work. Note that the version in infer is clang 7, not 6. You can try by messing with the CLANG_PREFIX, CLANG_INCLUDES, and CLANG variables when building the plugin manually (make -C facebook-clang-plugins/libtooling CLANG_PREFIX=... ...), possibly with LLVM_CXXFLAGS and LLVM_LDFLAGS too. Check out this Makefile.config in facebook-clong-plugins. The version on your system will need some symbols that are usually stripped by distributions though (in my experience). Also, clang 7 still being in development, it's unlikely that your distribution's version is at the same version exactly and some changing to the plugin may be necessary.

[rbartlensky]

@farao I had a similar problem, and I've done two things:

• built infer with NO_CMAKE_STRIP=1 ./build-infer.sh
• changed https://github.com/facebook/facebook-clang-plugins/blob/10eb1ac9bb9e94ae8332e84058f39699422a0e85/clang/setup.sh#L127 from /tmp/ to /home/my_username/ because I didn't have enough disk space

[farao]

Thanks, this is resolving my issue. And yes, choosing another CLANG_TMP_DIR was also very helpful - I think this should have another default than /tmp because /tmp is in most distributions now backed by ram and not disk.