[clang] [clang-tools-extra] [lldb] [clang] Reland: fix getTemplateInstantiationArgs (PR #208601)

[Erich Keane via cfe-commits]

erichkeane wrote:

> I am not planning on any further landings.
> 
> I created the PR in draft status if you will notice, with the intention that it will eventually contain the fixes to their repros, and then the PR would have moved to ready for review.
> 

Yep, I both saw that and understood that.  I marked it as 'needs revision' so that we don't merge this before the branch. Thanks in part to what you said below, I think this is too high risk by now to try to get in before the branch date.

> I don't think we want to set any rules about number of attempts, or even talk about number of attempts to land as a relevant metric of anything.

Agreed, but if there WAS a number, its probably less than 6 :) 

> As far as I know, all repros could have been reproduced on the first landing, and this could have gone a lot smoother if people didn't revert so fast, or if they did, if they actually provided repros the first time around.

That is the unfortunate nature of the project, folks work on a volunteer basis, so they understandably stop investigating once a revert happens.  Typically this isn't really problematic as there are rarely this many issues with a patch as this one was.  Also, to slightly disagree, there was at least 1 of the cycles where the 'fixup' is what caused the issue.

> This has been cooking for a long time, and it will soon be ready for 23.

I'm going to insist we aim for 24.


https://github.com/llvm/llvm-project/pull/208601