Should GHC default to -O1 ?

Duncan Coutts duncan.coutts at
Wed Nov 9 12:18:40 CET 2011

On 9 November 2011 00:17, Felipe Almeida Lessa <felipe.lessa at> wrote:
> On Tue, Nov 8, 2011 at 3:01 PM, Daniel Fischer
> < at> wrote:
>> On Tuesday 08 November 2011, 17:16:27, Simon Marlow wrote:
>>> most people know about 1, but I think 2 is probably less well-known.
>>> When in the edit-compile-debug cycle it really helps to have -O off,
>>> because your compiles will be so much quicker due to both factors 1 & 2.
>> Of course. So defaulting to -O1 would mean one has to specify -O0 in the
>> .cabal or Makefile resp. on the command line during development, which
>> certainly is an inconvenience.
> AFAIK, Cabal already uses -O1 by default.

Indeed, and cabal check / hackage upload complain if you put -O{n} in
your .cabal file.

The recommended method during development is to use:

$ cabal configure -O0


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