Re: Turning on -funbox-small-strict-fields by default in GHC 7.8

Reboxing would involve a two-word heap allocation. I guess it is not possible to argue that this cost would be amortized somewhere else, so you're right. Edward Excerpts from Johan Tibell's message of Thu Apr 25 16:01:49 -0700 2013:

On Thu, Apr 25, 2013 at 1:41 PM, Edward Z. Yang wrote:

...

SGTM. Actually, I think actually it should be quite simple to argue that there is no way for this change to degrade performance.

I think you could make up a case where it is a loss. It would boil down to repeated reboxing of a value pulled out of a strict field. In practice I think it's pretty hard. What did you have in mind?

-- Johan