[clang] [clang] Avoid -Wshadow warning when init-capture named same as class field (PR #74512)

[Erich Keane via cfe-commits]

erichkeane wrote:

> cc @erichkeane @AaronBallman

I looked through and don't see anything of concern to me that you haven't covered.  I am on the fence as to whether this warning makes sense to have in this situation.  

The point of the warning isn't that the language has a problem, it is that it is potentially confusing to readers.  And I'm not sure that it STOPS being confusing because of the lack of a capture of 'this'.

https://github.com/llvm/llvm-project/pull/74512