[GHC] #10134: Pattern Matching Causes Infinite Type Error

[GHC]

#10134: Pattern Matching Causes Infinite Type Error
-------------------------------------+-------------------------------------
        Reporter:  dongen            |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.8.4
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  None/Unknown      |  Unknown/Multiple
      Blocked By:                    |               Test Case:
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:
-------------------------------------+-------------------------------------

Comment (by simonpj):

 Aha.  The missing piece (which I found on the CLaSH page) is that the
 library in question is `clash-ghc` not `clash`.

 But I failed immediately
 {{{
 bash$ cabal install clash-ghc --with-
 ghc=/home/simonpj/5builds/HEAD-2/inplace/bin/ghc-stage2
 Resolving dependencies...
 cabal: Could not resolve dependencies:
 trying: clash-ghc-0.4.1 (user goal)
 trying: base-4.8.0.0/installed-inp... (dependency of clash-ghc-0.4.1)
 trying: unbound-0.4.3.1 (dependency of clash-ghc-0.4.1)
 trying: RepLib-0.5.3.3 (dependency of unbound-0.4.3.1)
 next goal: template-haskell (dependency of RepLib-0.5.3.3)
 rejecting: template-haskell-2.10.0.0/installed-inp... (conflict: RepLib =>
 template-haskell>=2.4 && <2.10)
 rejecting: template-haskell-2.9.0.0 (conflict: base==4.8.0.0/installed-
 inp...,
 template-haskell => base==4.7.*)
 rejecting: template-haskell-2.8.0.0 (conflict: base==4.8.0.0/installed-
 inp...,
 template-haskell => base==4.6.*)
 rejecting: template-haskell-2.7.0.0 (conflict: base==4.8.0.0/installed-
 inp...,
 template-haskell => base==4.5.*)
 rejecting: template-haskell-2.6.0.0 (conflict: base==4.8.0.0/installed-
 inp...,
 template-haskell => base==4.4.*)
 rejecting: template-haskell-2.5.0.0 (conflict: base==4.8.0.0/installed-
 inp...,
 template-haskell => base==4.3.*)
 rejecting: template-haskell-2.4.0.1 (conflict: base==4.8.0.0/installed-
 inp...,
 template-haskell => base==4.2.*)
 rejecting: template-haskell-2.4.0.0 (conflict: base==4.8.0.0/installed-
 inp...,
 template-haskell => base>=3 && <4.3)
 rejecting: template-haskell-2.3.0.1, 2.3.0.0, 2.2.0.0 (conflict: RepLib =>
 template-haskell>=2.4 && <2.10)
 Backjump limit reached (change with --max-backjumps).
 }}}
 I can't even see the code:
 {{{
 bash$  cabal unpack clash-ghc
 Downloading clash-ghc-0.4.1...
 cabal: <socket: 11>: resource vanished
 }}}
 The sad truth is that if it's too hard to reproduce a bug, I just move on
 to something else.  I'd love to look at this, but I can only do so if I
 can reproduce it, and currently I can't.  If you feel motivated to work on
 a smaller test case, one that doesn't depend on so much extra stuff, then
 that'd be great. Otherwise we are stalled.

 Simon

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10134#comment:12>
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