[PATCH] D22073: libc++: test lock-free atomic alignment

[JF Bastien via cfe-commits]

jfb added a comment.

In http://reviews.llvm.org/D22073#481402, @EricWF wrote:

> - The test should be moved to `test/libcxx/atomics/atomics.align` since it's libc++ specific.


Done.

> - Please give the anonymous struct declarations unique names. `T1`, `T2`, ..., `TN` is fine. Currently they all mangle to `main::type` in diagnostic output.


Done. I'll update test/std/atomics/atomics.lockfree/isalwayslockfree.pass.cpp in a separate change to do the same (I wrote that one as well, didn't name the structs at the time).

> - The test fails to link on my machine unless I manually links `-latomic`. The tests currently don't link `-latomic` and I don't want to turn it on by default. I'll try and fix this.


OK, LMK if I can do anything. I build with:

  cmake -G Ninja ../llvm \
    -DCMAKE_EXPORT_COMPILE_COMMANDS=ON \
    -DLLVM_BUILD_TESTS=ON \
    -DCMAKE_BUILD_TYPE=RelWithDebInfo \
    -DLLVM_ENABLE_ASSERTIONS=ON \
    -DCMAKE_C_COMPILER=/path/to/bin/clang \
    -DCMAKE_CXX_COMPILER=/path/to/bin/clang++ \
    -DLLVM_PATH=/path/to/llvm \
    -DLIBCXX_CXX_ABI=libcxxabi \
    -DLIBCXX_CXX_ABI_INCLUDE_PATHS=/path/to/llvm/projects/libcxxabi/include \
    -DLIBCXX_HAS_ATOMIC_LIB=True

I found it weird to have to specify `-DLIBCXX_HAS_ATOMIC_LIB=True` because it tells me that libc++ isn't tested *at all* with GCCMM atomic runtime functions <https://gcc.gnu.org/wiki/Atomic/GCCMM>! I was going to look into that afterwards.

IMO we may want to always link to it.


http://reviews.llvm.org/D22073