[GHC] #9567: tc124 fails as '*** Core Lint errors : in result of Simplifier ***' in WAY=optasm

[GHC]

#9567: tc124 fails as '*** Core Lint errors : in result of Simplifier ***' in
WAY=optasm
-------------------------------------+-------------------------------------
       Reporter:  slyfox             |                   Owner:
           Type:  bug                |                  Status:  new
       Priority:  normal             |               Milestone:
      Component:  Compiler           |                 Version:  7.9
       Keywords:                     |        Operating System:
   Architecture:  x86_64 (amd64)     |  Unknown/Multiple
     Difficulty:  Unknown            |         Type of failure:  GHC
     Blocked By:                     |  rejects valid program
Related Tickets:                     |               Test Case:  tc124
                                     |                Blocking:
                                     |  Differential Revisions:
-------------------------------------+-------------------------------------
 ghc-HEAD:

 {{{
 $ make fulltest TEST="tc124" WAY=optasm

 =====> tc124(optasm) 3136 of 4101 [0, 0, 0]
 cd ./typecheck/should_compile && '/home/slyfox/dev/git/ghc-
 validate/inplace/bin/ghc-stage2' -fforce-recomp -dcore-lint -dcmm-lint
 -dno-debug-output -no-user-package-db -rtsopts -fno-ghci-history -c
 tc124.hs -O -fasm  -fno-warn-incomplete-patterns >tc124.comp.stderr 2>&1
 Compile failed (status 256) errors were:
 *** Core Lint errors : in result of Simplifier ***
 <no location info>: Warning:
     In the type ‘a_12 -> a_aia -> a_aia’
     @ a_12 is out of scope
 *** Offending Program ***
 Foo.g :: Foo.T -> Foo.T
 [LclIdX,
  Arity=1,
  Str=DmdType,
  Unf=Unf{Src=<vanilla>, TopLvl=True, Value=True, ConLike=True,
          WorkFree=True, Expandable=True, Guidance=IF_ARGS [20] 40 30}]
 Foo.g =
   \ (t_ahr :: Foo.T) ->
     case t_ahr of _ [Occ=Dead] { Foo.T ds_dlB ds_dlC ->
     Foo.T
       ds_dlB
       (\ (@ a_ai4) (@ b_ai5) _ [Occ=Dead] (y_aht :: b_ai5) -> y_aht)
     }
 ...
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9567>
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