[GHC] #10829: Simplification in the RHS of rules

[GHC]

#10829: Simplification in the RHS of rules
-------------------------------------+-------------------------------------
        Reporter:  afarmer           |                Owner:
            Type:  bug               |               Status:  patch
        Priority:  high              |            Milestone:  7.10.3
       Component:  Compiler          |              Version:  7.10.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #10528            |  Differential Rev(s):  Phab:D1246
-------------------------------------+-------------------------------------

Comment (by afarmer):

 Rebased onto most recent master and did a `./validate --slow` on both
 master and this patch. The one additional test that fails is T7785, so I'm
 looking into it now.

 {{{
 =====> T7785(optasm) 1 of 1 [0, 0, 0]
 cd ./simplCore/should_compile &&  "/data/users/anfarmer/head/inplace/bin
 /ghc-stage2" -c T7785.hs -fforce-recomp -dcore-lint -dcmm-lint -dno-debug-
 output -no-user-package-db -rtsopts -fno-warn-tabs -fno-warn-missed-
 specialisations -fno-ghci-history  -O -fasm -ddump-rules >
 T7785.comp.stderr 2>&1
 Actual stderr output differs from expected:
 --- ./simplCore/should_compile/T7785.stderr.normalised  2015-10-06
 11:10:41.550769587 -0700
 +++ ./simplCore/should_compile/T7785.comp.stderr.normalised     2015-10-06
 11:10:41.550769587 -0700
 @@ -4,5 +4,3 @@
      forall ($dMyFunctor :: MyFunctor []) (irred :: Domain [] Int).
        shared @ [] $dMyFunctor irred
        = bar_$sshared
 -"SPEC/Foo myfmap @ []" [ALWAYS]
 -    forall (tpl :: MyFunctor []). myfmap @ [] tpl = $cmyfmap
 *** unexpected failure for T7785(optasm)
 }}}

 I did a preliminary stackage LTS 3.7 build (with 7.10.2+patch) and it
 looked positive (everything seemed to be building), but the VM ran out of
 disk and didn't build the last 300 or so packages. Going to restart that
 process on another machine and report back.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10829#comment:19>
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