On Sat, Jan 31, 2015 at 10:47 AM, Reid Barton wrote:

On Sat, Jan 31, 2015 at 10:16 AM, Brandon Allbery wrote:

...

On Sat, Jan 31, 2015 at 8:34 AM, George Colpitts < george.colpitts@gmail.com> wrote:

...

cabal install *--allow-newer=base* accelerate

Never safe, because base contains the runtime and the runtime and the compiler are very tightly tied together. Crashes are not surprising.

Actually it should always be safe: --allow-newer=base is essentially the equivalent of removing the upper bound on base from the .cabal file (of every package that was installed during that run).

However, I'm quite confused about something, namely that as far as I can tell, neither accelerate nor any of its dependencies contain a module Data.Label.Base. What package was GHC trying to build when it crashed?

Oops, I was running the wrong command: it's in fclabels. Please file a bug report and attach the output of `cabal install --ghc-options=-v fclabels`, thanks! Regards, Reid Barton

On Sat, Jan 31, 2015 at 11:09 AM, Herbert Valerio Riedel

wrote:

On 2015-01-31 at 14:34:35 +0100, George Colpitts wrote:

...

Maybe this is something I shouldn't be doing, but I thought it was worth mentioning in case I have found a compiler bug. Should I file a bug for this?

cabal install *--allow-newer=base* accelerate ... [10 of 10] Compiling Data.Label.Base ( src/Data/Label/Base.hs, dist/build/Data/Label/Base.o ) ghc: internal error: PAP object entered! (GHC version 7.10.0.20150123 for x86_64_apple_darwin) Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug

I suspect this has to do with `--allow-newer=base` allowing template-haskell-2.9.0.0 to be re-installed (which then becomes a build-dependency of `fclabels`). GHC 7.10, however, comes with template-haskell-2.10.0.0

Ah yes, you're exactly right. I didn't encounter this when I tried to reproduce the issue because I have a bunch of lines like "constraint: template-haskell installed" in my .cabal/config file. Regards, Reid Barton