[compiler-rt] [libcxx] CompilerRT: Normalize COMPILER_RT_DEFAULT_TARGET_TRIPLE (PR #89234)

[Peter Waller via llvm-commits]

peterwaller-arm wrote:

I've posted an RFC on the topic to discourse: https://discourse.llvm.org/t/rfc-baremetal-target-triple-normalization/78524

https://github.com/llvm/llvm-project/pull/89234