GHC internal error
marlowsd at gmail.com
Tue Apr 6 10:10:53 EDT 2010
If you aren't using anything unsafe, then it is a bug. Even if you are
using something unsafe, it might still be a bug; either way if you can
narrow down to the smallest program (+data) that crashes that would be
Does the result change if you use different GC settings? I like to use
+RTS -A8k to force GC to happen as often as possible, it helps to flush
out GC problems earlier.
On 05/04/2010 20:05, Philip Weaver wrote:
> Yes, I can do that. However, I'm hoping to narrow it down a lot more so
> that I can file a more useful bug report.
> Since sending my last email, I have learned a bit more:
> I was using 'fail' (the Monad being ReaderT . StateT . ST) to report
> errors. If I replace 'fail msg' with 'error msg' or 'return (error
> msg)', then the aforementioned internal error does not occur.
> In some cases, the program dies with the aforementioned error. In other
> cases, it segfaults.
> - Philip
> On Mon, Apr 5, 2010 at 11:59 AM, Don Stewart <dons at galois.com
> <mailto:dons at galois.com>> wrote:
> Any 'internal error' is almost certainly an RTS or compiler bug. Can you
> make a bug report?
> > Hi all,
> > A program that I built with GHC is crashing at runtime with the
> > error:
> > internal error: eval_thunk_selector: strange selectee 12
> > I have not found much via Google, just an old post regarding ghc
> 6.0 that
> > recommends cleaning and rebuilding. I have cleaned the build
> directory and
> > re-built the executable, and I still get the error.
> > The program is a compiler, and this error began showing up after
> I added
> > support for memoization of results using the ST Monad and STRefs.
> For example,
> > the following function creates a reference to a thunk:
> > newMutableRef m
> > = do ref <- newSTRef $ error "access ref too soon!"
> > let m' = do r <- m
> > writeSTRef ref (return r)
> > return r
> > writeSTRef ref m'
> > return $ ref
> > Here's some information about my system:
> > • GHC 6.12.1
> > • Mac OS X 10.6.3 (Snow Leopard)
> > So, what could cause this error? Any suggestions that can help
> me narrow down
> > the problem would be greatly appreciated. If this is in fact a
> GHC bug, I'd
> > like to find a workaround for now and also reproduce it in a
> small example so I
> > can file a bug report.
> > - Philip
> > _______________________________________________
> > Glasgow-haskell-users mailing list
> > Glasgow-haskell-users at haskell.org
> <mailto:Glasgow-haskell-users at haskell.org>
> > http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
> Glasgow-haskell-users mailing list
> Glasgow-haskell-users at haskell.org
More information about the Glasgow-haskell-users