[libcxx-commits] [libcxxabi] [ItaniumDemangle] reject A-F in FP literals (PR #82864)

[Fangrui Song via libcxx-commits]

https://github.com/MaskRay approved this pull request.

llvm/include/llvm/Demangle/ItaniumDemangle.h contains a copy that can be synced later.

https://github.com/llvm/llvm-project/pull/82864