[libcxx-commits] [clang] [libcxx] [Clang] Normalize constraints before checking for satisfaction (PR #161671)

[Aaron Ballman via libcxx-commits]

AaronBallman wrote:

> I'm not sure how to proceed here. A 16% build time increase (as mentioned up-thread) is very significant for us.
> 
> @AaronBallman do you have any thoughts here?

16% is a bigger performance regression than I think we were anticipating.

> I did see that #61811 mention "We should get performance data for that change and give feedback to WG21 if it looks like this is going to have a significant performance impact." So it sounds like this was somewhat anticipated?

I think we expected a performance hit, but more like 1-3%, not 10+%; that's significant enough that if we can't solve it, it should be feedback given to WG21 because that feels like too much of a regression to swallow. CC @cor3ntin (it may be a while before he responds, the dev conference is next week and WG21 meetings are the week after).

https://github.com/llvm/llvm-project/pull/161671