[GHC] #2273: inlining defeats seq

[GHC]

#2273: inlining defeats seq
-------------------------------+--------------------------------------------
  Reporter:  igloo             |          Owner:                  
      Type:  bug               |         Status:  new             
  Priority:  lowest            |      Milestone:  7.6.2           
 Component:  Compiler          |        Version:  6.9             
Resolution:                    |       Keywords:                  
        Os:  Unknown/Multiple  |   Architecture:  Unknown/Multiple
   Failure:  None/Unknown      |     Difficulty:  Unknown         
  Testcase:                    |      Blockedby:                  
  Blocking:                    |        Related:                  
-------------------------------+--------------------------------------------

Comment(by morabbin):

 Seems to work as desired with 7.6.1:
 {{{
 ghc -O -ddump-simpl -ddump-stg -c T2273.hs
 }}}
 yields (in the STG code):
 {{{
 [GblId, Arity=2, Str=DmdType S(S)L, Unf=OtherCon []] =
     \r srt:(0,*bitmap*) [env_sxC s_sxP]
         case env_sxC of wild_sxO {
           Q.TcLclEnv ds_sxF ->
               case
                   case ds_sxF of _ {
                     Q.Comp -> Q.tcExtendIdEnv3;
                     Q.Splice l_sxI -> l_sxI;
                     Q.Brack l_sxK -> l_sxK;
                   }
               of
               level_sxN
               { GHC.Types.I# ipv_syf ->
                     Q.tc_extend_local_id_env level_sxN wild_sxO s_sxP;
               };
         };
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2273#comment:21>
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