[Haskell-cafe] faster compiling for ghc

[Nicolas Pouillard]

Excerpts from Jason Dagit's message of Fri Nov 13 02:25:06 +0100 2009:
> On Thu, Nov 12, 2009 at 2:57 AM, Neil Mitchell <ndmitchell at gmail.com> wrote:
> 
> > Hi,
> >
> > I'd really love a faster GHC! I spend hours every day waiting for GHC,
> > so any improvements would be most welcome.
> >
> 
> Has anyone built a profiling enabled GHC to get data on where GHC spends
> time during compilation?
> 
> >
> > I remember when developing Yhc on a really low powered computer, it
> > had around 200 modules and loaded from scratch (with all the Prelude
> > etc) in about 3 seconds on Hugs. ghc --make took about that long to
> > start compiling the first file, and I think a complete compile was
> > around 5 minutes. It's one of the main reasons I stuck with Hugs for
> > so long.
> >
> > Running GHC in parallel with --make would be nice, but I find on
> > Windows that the link time is the bottleneck for most projects.
> >
> 
> Yes, when GHC calls GNU ld, it can be very costly.  In my experience, on a

I confirm that I also had this experience on Arch Linux, GNU ld was allocating
Gigs of memory, however this is very hard to reproduce. Actually I've wrapped
/usr/bin/ld with a timeout :)

-- 
Nicolas Pouillard
http://nicolaspouillard.fr