[GHC] #7436: Derived Foldable and Traversable instances become extremely inefficient due to eta-expansion

[Ian Lynagh]

Hi Simon,

On Tue, Apr 16, 2013 at 03:55:16PM -0000, GHC wrote:
> #7436: Derived Foldable and Traversable instances become extremely inefficient due
> to eta-expansion
> 
> Comment(by simonpj):
> 
>  This one is fixed, just awaiting merging into 7.6.3

My suggestion was that we only fix #7748 in 7.6.3, as that seems to be a
show-stopper. There are several other fixes that we would ordinarily
merge into 7.6.3, but every change has a risk of causing a regression
(after all, 7.6.2 made #7748 worse), and we want to get 7.6.3 out as
quickly as possible (so as not to hold up the HP release) so we don't
have the luxury of being able to have a long testing/RC phase.

But if you think it's important enough, and the fix safe enough, please
let me know and I'll merge it.


Thanks
Ian