[PATCH] D24082: [CMake] Fix libc++abi arm build w/o libunwind.

[Eric Fiselier via cfe-commits]

EricWF added a comment.

Is `ON` the right default for ARM? If so please apply the inline comment to fix the default settings.. Otherwise this LGTM.



================
Comment at: CMakeLists.txt:117
 option(LIBCXXABI_ENABLE_WERROR "Fail and stop if a warning is triggered." OFF)
 option(LIBCXXABI_USE_LLVM_UNWINDER "Build and use the LLVM unwinder." OFF)
 option(LIBCXXABI_USE_COMPILER_RT "Use compiler-rt instead of libgcc" OFF)
----------------
```
cmake_dependent_option(LIBCXXABI_USE_LLVM_UNWINDER "Build and use the LLVM unwinder" OFF
                                           "LLVM_NATIVE_ARCH MATCHES ARM" ON)
```

And don't forget to add the include for cmake_dependent_option somewhere above!


https://reviews.llvm.org/D24082