[clang] [clang-tools-extra] [clang] [Sema] Preserve nested name specifier prefix in MemberPointerType (PR #118236)

[Nathan Ridge via cfe-commits]

HighCommander4 wrote:

I updated the patch to do the wrapping into `ElaboratedType` even if a prefix isn't present, and updated the various failing tests accordingly.

I haven't added an assert, as explained in the previous comment.

https://github.com/llvm/llvm-project/pull/118236