[Pkg-haskell-maintainers] Bug#654618: xmobar: FTBFS on many arches, missing library HSrts_thr

[Apollon Oikonomopoulos]

On 00:24 Thu 05 Jan     , peter green wrote:
> >xmobar FTBFS on many arches, due to missing linking library:
> >
> >Linking dist/build/xmobar/xmobar ...
> >/usr/bin/ld: cannot find -lHSrts_thr
> >
> >Please look into this.
> That libary simply doesn't seem to exist on the architectures
> in question (armel, armhf, mips, mipsel, s390, s390x and sparc)
> contacting the ghc maintainers to determine if this is a bug in
> ghc (which provides that libary on amd64) or if there is something
> that needs to be fixed on the application side.
> 
> P.S. i'm just taking a look at armhf build failures here, I don't
> have anything to do with the package.
> 

Hi all,

I'm CCing the upstream maintainer as well.

According to ghc6's changelog.Debian, the threaded runtime was disabled for
all non-x86/amd64 architectures in 6.6 (some 5+ years ago). xmobar didn't
require a threaded runtime to run as it was using lightweight threads,
however in upstream commit dbf4ea77 (between 0.13 and 0.14), a single ForkOS
call to handle the XRandR events was introduced. The ForkOS call spawns real
OS threads and requires explicit linking against the threaded runtime, which
is unavailable in most architectures.

José, could this ForkOS call be replaced with a ForkIO call? From what I
gather from the Control.Concurrent documentation[1], ForkOS is only needed
when using a foreign call that needs thread-local storage. Any ideas?

Regards,
Apollon

[1] http://www.haskell.org/ghc/docs/7.0.4/html/libraries/base-4.3.1.0/Control-Concurrent.html