[GHC] #10934: Iface type variable out of scope

[GHC]

#10934: Iface type variable out of scope
-------------------------------------+-------------------------------------
        Reporter:  mjmrotek          |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.10.2
      Resolution:                    |             Keywords:  interface
Operating System:  Linux             |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash                              |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
-------------------------------------+-------------------------------------

Comment (by thomie):

 Similar bugs were closed because of lack of reproducability (#9584,
 #7958), but I can reproduce your problem.

 * clone https://github.com/marcinmrotek/pipes-key-value-csv at commit
 5719db5cc7eeecf2a0690ca5627ae6bd9500280c
 * uncommented the line `-- . KV.foldHeader` in `test/Test/KeyValue.hs`
 * `cabal install --dependencies-only`
 * `cabal test`


 I used the following tools:
 * ghc-7.10.2
 * cabal-install version 1.22.6.0
 * version 1.22.4.0 of the Cabal library
 * packages from http://www.stackage.org/snapshot/lts-3.4

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10934#comment:1>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler