[GHC] #14116: STG lint error while compiling master (was: Core lint error while compiling master)

[GHC]

#14116: STG lint error while compiling master
-------------------------------------+-------------------------------------
        Reporter:  bgamari           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:
       Component:  Compiler          |              Version:  8.2.1
      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:                    |
-------------------------------------+-------------------------------------
Description changed by bgamari:

Old description:

> 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 ***
> ...
> }}}

New description:

 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 STG 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#comment:2>
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