What type of performance regression testing does GHC go through?

[Tom Ellis]

A user posted the following to the ghc-proposals repository.  Both JB
and RAE suggested ghc-devs as a more appropriate forum.  Since I have
no idea whether the user has even ever used a mailing list before I
thought I would lower the activation energy by posting their message
for them.

https://github.com/ghc-proposals/ghc-proposals/issues/410

> Hi,
> 
> Does the GHC release or development process include regression
> testing for performance?
> 
> Is this the place to discuss ideas for implementing such a thing and
> to eventually craft a proposal?
> 
> I believe the performance impact of changes to GHC needs to be
> verified/validated before release. I also believe this would be
> feasible if we tracked metrics on building a wide variety of
> real-world packages. Using real-world packages is one of the best
> ways to see the actual impact users will experience. It's also a
> great way to broaden the scope of tests, particularly with the
> combination of language pragmas and enabled features within the
> compiler.