[GHC] #13991: I was building/testing a haskell project using stack ..suddenly I see the following output. Also attached the project

[GHC]

#13991: I was building/testing a haskell project using stack ..suddenly I see the
following output. Also attached the project
-------------------------------------+-------------------------------------
        Reporter:  chandrakoduru     |                Owner:  (none)
            Type:  bug               |               Status:  infoneeded
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by RyanGlScott):

 * status:  new => infoneeded


Old description:

> putting-haskell-to-test-0.0.1.0: build (lib + test)
> Preprocessing library putting-haskell-to-test-0.0.1.0...
> Preprocessing test suite 'HUnitTest' for putting-haskell-to-
> test-0.0.1.0...
> [1 of 1] Compiling Main             ( test/HUnitTest/Spec.hs, .stack-
> work/dist/x86_64-linux/Cabal-1.24.2.0/build/HUnitTest/HUnitTest-
> tmp/Main.o )
> ghc: panic! (the 'impossible' happened)
>   (GHC version 8.0.2 for x86_64-unknown-linux):
>         initTc: unsolved constraints
>   WC {wc_insol =
>         [W] @?=_a1lM :: t_a1lL[tau:1] (CHoleCan: @?=)
>         [W] testCase_a1m2 :: t_a1m1[tau:1] (CHoleCan: testCase)
>         [W] simpleMathFunction_a1mb :: t_a1ma[tau:1] (CHoleCan:
> simpleMathFunction)
>         [W] @?=_a1xp :: t_a1xo[tau:1] (CHoleCan: @?=)
>         [W] testCase_a1xB :: t_a1xA[tau:1] (CHoleCan: testCase)
>         [W] simpleMathFunction_a1xK :: t_a1xJ[tau:1] (CHoleCan:
> simpleMathFunction)}
>
> Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
>
> Progress: 1/2
> --  While building package putting-haskell-to-test-0.0.1.0 using:
>       /home/local/ANT/chandrak/.stack/setup-exe-cache/x86_64-linux/Cabal-
> simple_mPHDZzAJ_1.24.2.0_ghc-8.0.2 --builddir=.stack-
> work/dist/x86_64-linux/Cabal-1.24.2.0 build lib:putting-haskell-to-test
> test:HUnitTest --ghc-options " -ddump-hi -ddump-to-file"
>     Process exited with code: ExitFailure 1

New description:

 {{{
 putting-haskell-to-test-0.0.1.0: build (lib + test)
 Preprocessing library putting-haskell-to-test-0.0.1.0...
 Preprocessing test suite 'HUnitTest' for putting-haskell-to-
 test-0.0.1.0...
 [1 of 1] Compiling Main             ( test/HUnitTest/Spec.hs, .stack-
 work/dist/x86_64-linux/Cabal-1.24.2.0/build/HUnitTest/HUnitTest-tmp/Main.o
 )
 ghc: panic! (the 'impossible' happened)
   (GHC version 8.0.2 for x86_64-unknown-linux):
         initTc: unsolved constraints
   WC {wc_insol =
         [W] @?=_a1lM :: t_a1lL[tau:1] (CHoleCan: @?=)
         [W] testCase_a1m2 :: t_a1m1[tau:1] (CHoleCan: testCase)
         [W] simpleMathFunction_a1mb :: t_a1ma[tau:1] (CHoleCan:
 simpleMathFunction)
         [W] @?=_a1xp :: t_a1xo[tau:1] (CHoleCan: @?=)
         [W] testCase_a1xB :: t_a1xA[tau:1] (CHoleCan: testCase)
         [W] simpleMathFunction_a1xK :: t_a1xJ[tau:1] (CHoleCan:
 simpleMathFunction)}

 Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

 Progress: 1/2
 --  While building package putting-haskell-to-test-0.0.1.0 using:
       /home/local/ANT/chandrak/.stack/setup-exe-cache/x86_64-linux/Cabal-
 simple_mPHDZzAJ_1.24.2.0_ghc-8.0.2 --builddir=.stack-
 work/dist/x86_64-linux/Cabal-1.24.2.0 build lib:putting-haskell-to-test
 test:HUnitTest --ghc-options " -ddump-hi -ddump-to-file"
     Process exited with code: ExitFailure 1
 }}}

--

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13991#comment:4>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler