Sending this for discussion. It works fine for me...
1 patch for repository http://darcs.net/screened:
patch 8f3b7bb7685d16003ba26050397b3022d0427119
Author: Ben Franksen <ben.franksen@online.de>
Date: Fri Jul 19 17:55:14 CEST 2019
* remove our own optimisation settings in darcs.cabal
Letting cabal be aware of optimisation makes it easier to switch between
optimised and unoptimised builds, since cabal nowadays puts unoptimised
builds in a separate directory.
I tested with a number CPU-intensive test runs (darcs-test -t conflict) that
this causes no performance regressions: the default optimisation level
chosen by cabal (-O1) gives the same or better results than the -O2 we
passed explicitly.