[libcxx-commits] [libcxx] [libcxxabi] [libcxx][cmake] Allow using FatLTO in libc++ builds (PR #112277)

[Paul Kirth via libcxx-commits]

ilovepi wrote:

@petrhosek originally I had used a helper function to do add these flags in the libcxx top level cmake, but that didn't work (similar to this https://github.com/llvm/llvm-project/blob/d0d54fa066d224d1338f65b6e048bdff64feca37/libcxx/CMakeLists.txt#L567).  I'm pretty confused why that approach failed, even when use `add_flags` directly, or appending to the list, vs. doing something here.

https://github.com/llvm/llvm-project/pull/112277