[GHC] #14116: Core lint error while compiling master

[GHC]

#14116: Core lint error while compiling master
-------------------------------------+-------------------------------------
           Reporter:  bgamari        |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  high           |         Milestone:
          Component:  Compiler       |           Version:  8.2.1
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 While compiling e054c5f06451def4437d9d770ae156f034796c59 with the
 following `build.mk`,
 {{{
 BuildFlavour = devel2
 include mk/flavours/$(BuildFlavour).mk

 GhcStage2HcOpts += -eventlog
 GhcStage1HcOpts += -eventlog

 GhcLibHcOpts += -g3 -ddump-to-file -ddump-stg -dcore-lint -dstg-lint
 -dcmm-lint
 GhcRtsHcOpts += -g3
 GhcStage2HcOpts += -g3 -ddump-to-file -ddump-stg -dcore-lint -dstg-lint
 -dcmm-lint
 }}}

 I encountered this Core lint failure while compiling `PprColour`,
 {{{
 stgEqType: unequal
   PprColour
   [Char]
 ghc-stage1: panic! (the 'impossible' happened)
   (GHC version 8.3.20170815 for x86_64-unknown-linux):
           *** Stg Lint ErrMsgs: in Stg2Stg ***
   compiler/utils/PprColour.hs:62:1: warning:
        [RHS of defaultScheme :: Scheme]
       In a RHS constructor application, con type doesn't match arg types:
       Constructor type:
           PprColour
           -> PprColour
           -> PprColour
           -> PprColour
           -> PprColour
           -> PprColour
           -> Scheme
       Arg types:
           [Char]
           PprColour
           String
           String
           String
           String
   *** Offending Program ***
 ...
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14116>
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