[clang] [AST] Iterate redecls starting from the canonical one in getRawCommentsForAnyRedecl() (PR #108475)

[Younan Zhang via cfe-commits]

https://github.com/zyn0217 approved this pull request.

Thanks for working on this! I think this probably needs a release note, otherwise it looks good on the whole.

Please give other folks some time before merging it, and I invited @AaronBallman for the second pair of eyes.

https://github.com/llvm/llvm-project/pull/108475