I want to update the SIG on various news:
* ghc-7.4.2 and haskell-platform-2012.4
I have started work locally testing updating rawhide to ghc-7.4.2
and haskell-platform-2012.4 RC2. If people want I can upload
my local ghc-7.4.2 and haskell-platform builds for testing.
Overall the results so far are fairly good.
Only a few remaining packages have problems:
- Agda (constructor issue)
- happstack-server (blaze-html or new deps)
- hledger-lib-0.19 needs shakespeare-text (review pending)
- xss-sanitize (css-text not imported yet!)
but they should be fixable by F19 time.
I plan to build ghc-7.4.2 for Rawhide within the next week.
* Updating packages to latest versions
We have a lot of packages that need a version refresh.
Now is a great time to bump your packages in git master.
Building for rawhide is also ok but not really necessary right now
since everything will need rebuilding shortly soon anyway.
I really need your help with this, but if you don't have time to do it
I will start touching packages generally in the coming week or so.
* cabal-rpm update
I have been using cabal-rpm to refresh a few packages by hand
and I am going to release 0.6.5 soon with some smaller tweaks
and improvements: the biggest visible change being no longer using
version-ranged BRs since I think this has too much maintenance
overhead at least until cabal-rpm can do updating of packages.
* Haskell Platform and ghc versions
I am wondering how closely we should follow Haskell Platform going
forward since the releases are not well synced with Fedora's schedule
and upstream so far refused to shift its schedule...
As such I quite like following HP - it is gives us a certain stability
and certainty of base versions, but also understand that some people
want to have the latest versions available and live on the bleeding edge.
Personally I am leaning towards doing more backporting - I am thinking
to backport ghc-7.4.2 and haskell-platform-2012.4 to F18 for example
(after it has gone to rawhide). If there is demand we could also
backport ghc-7.4.1 to F17 perhaps or I could make a yum repo for it
from the F18 packages. Ubuntu-12.10 just recently shipped with ghc-7.4.2.
What do people think? How important is it to have the official
haskell-platform in Fedora?
Another side issue is that I somewhat cavalierly made haskell-platform
into a monolithic package in F18, thinking this would decrease its update/build time.
This unfortunately means if we weren't going to follow HP closely we
would probably need to re-review all the HP packages again... :-/
I wanted to let you know that I finally got round to resubmitting 
the revised Haskell Packaging Guidelines  again to FPC for review.
I will try not to let it slip again this time! Then hopefully soon
we can finally get our current packaging officially approved, and
maybe also opening our reviews to a wider audience of reviewers.
Comments are of course also welcome from members of the SIG,
Fedora Contributors and the Community.
I wrote a multithreaded GUI program for a research project using gtk2hs,
and it works fine on fedora 17, which uses ghc 7.0.4. It crashes almost as
soon as it starts when compiled and run on fedora 18 (ghc 7.4.1). There's
a message on the console that it was killed because of a segmentation fault
and that's about all it tells me. I tracked down the code that causes
crash, and it seems to happen because I add an action to the gtk loop:
timeoutAddFull action ...
and the crash happens when the action runs the first time. I thought it
was a bug in ghc 7.4.1, because I found a bug report that talks about a
crash involving STM and multithreading, and supposedly was fixed in 7.4.2.
So I set up a virtual machine and installed fedora 18 then upgraded it to
rawhide to try my program under 7.4.2. But, the same crash happens on my
However, it happened that I had to disable selinux on my rawhide machine
using the boot command line because something started going wrong, still
not sure what (hey, it's rawhide). Now my program does not crash. I just
tested this on my fedora 18 laptop (still ghc 7.4.1) using both the version
compiled on fedora 18 and the files from where I compiled it on rawhide:
when I disable selinux, my program runs fine, but when it's enabled (even
if set to permissive rather than enforcing) my program seg faults.
There's nothing useful in /var/log/messages, no indication of what selinux
is unhappy about. I did find this:
at least in that problem, there was a definite error message about memory
mapping, and I'm not getting one.
So as best I can tell, ghc 7.4.1&2 must both be doing something strange,
maybe marking some piece of memory as data instead of code, maybe when
performing calls to gtk, maybe in building thunks for use by
timeoutAddFull, and eventually triggering a security problem.
My program is huge, and I'm trying to narrow down the problem, but it must
be some unexpected interaction between ghc's newer run time systems, gtk,
I've posted a bug report with a small program that generates the same error:
In the mean time, has anyone else run into this problem?
-- Garrett Mitchener