[GHC] #10527: Panic Simplifier ticks exhausted with type families

[GHC]

#10527: Panic Simplifier ticks exhausted with type families
-------------------------------------+-------------------------------------
        Reporter:  sopvop            |                   Owner:  simonpj
            Type:  bug               |                  Status:  new
        Priority:  highest           |               Milestone:  7.10.2
       Component:  Compiler          |                 Version:  7.10.1-rc1
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  None/Unknown      |  Unknown/Multiple
      Blocked By:                    |               Test Case:
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:
-------------------------------------+-------------------------------------

Comment (by bgamari):

 It appears that the following failures are triggered by the fix on
 `ghc-7.10`,

  * `simplCore/should_compile  T4945 [bad stdout] (normal)`
 {{{
 =====> T4945(normal) 1533 of 4449 [0, 1, 0]
 cd ./simplCore/should_compile && $MAKE -s --no-print-directory T4945
 </dev/null > T4945.run.stdout 2> T4945.run.stderr
 Actual stdout output differs from expected:
 --- ./simplCore/should_compile/T4945.stdout     2015-07-06
 17:16:38.859135774 -0400
 +++ ./simplCore/should_compile/T4945.run.stdout 2015-07-07
 03:57:30.592499506 -0400
 @@ -1,7 +0,0 @@
 -                               -> STUArray RealWorld Int Int
 -                              (ipv3 [OS=OneShot] :: STUArray RealWorld
 Int Int) ->
 -                                          case ipv3 of _ [Occ=Dead] {
 STUArray ds5 ds6 dt ds7 ->
 -                                  (Data.Array.Base.STUArray
 -                                  (Data.Array.Base.STUArray
 -                                  (Data.Array.Base.STUArray
 -                                  (Data.Array.Base.STUArray
 *** unexpected failure for T4945(normal)
 }}}
  * `perf/should_run  T5113 [stat not good enough] (normal)`
 {{{
 =====> T5113(normal) 2426 of 4449 [0, 2, 0]
 cd ./perf/should_run &&  "/home/ben/trees/ghc/ghc-7.10/inplace/bin/ghc-
 stage2" -o T5113 T5113.hs -fforce-recomp -dcore-lint -dcmm-lint -dno-
 debug-output -no-user-package-db -rtsopts -fno-warn-tabs -fno-ghci-history
 -O > T5113.comp.stderr 2>&1
 cd ./perf/should_run && ./T5113  +RTS -V0 -tT5113.stats --machine-readable
 -RTS   </dev/null > T5113.run.stdout 2> T5113.run.stderr
 bytes allocated value is too high:
     Expected    T5113(normal) bytes allocated:   8000000 +/-5%
     Lower bound T5113(normal) bytes allocated:   7600000
     Upper bound T5113(normal) bytes allocated:   8400000
     Actual      T5113(normal) bytes allocated: 806747568
     Deviation   T5113(normal) bytes allocated:    9984.3 %
 *** unexpected stat test failure for T5113(normal)
 }}}
  * `perf/compiler    T9961 [stat too good] (normal)`
 {{{
 =====> T9961(normal) 2474 of 4449 [0, 2, 0]
 cd ./perf/compiler &&  "/home/ben/trees/ghc/ghc-7.10/inplace/bin/ghc-
 stage2" -c T9961.hs -fforce-recomp -dno-debug-output -no-user-package-db
 -rtsopts -fno-warn-tabs -fno-ghci-history  -O +RTS -V0 -tT9961.comp.stats
 --machine-readable -RTS > T9961.comp.stderr 2>&1
 bytes allocated value is too low:
 (If this is because you have improved GHC, please
 update the test so that GHC doesn't regress again)
     Expected    T9961(normal) bytes allocated: 663978160 +/-5%
     Lower bound T9961(normal) bytes allocated: 630779252
     Upper bound T9961(normal) bytes allocated: 697177068
     Actual      T9961(normal) bytes allocated: 616521968
     Deviation   T9961(normal) bytes allocated:      -7.1 %
 *** unexpected stat test failure for T9961(normal)
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10527#comment:25>
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