[GHC] #8613: simplifier ticks exhausted

[GHC]

#8613: simplifier ticks exhausted
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       Reporter:  guest           |             Owner:
           Type:  bug             |            Status:  new
       Priority:  normal          |         Milestone:
      Component:  Compiler        |           Version:  7.6.3
       Keywords:                  |  Operating System:  MacOS X
   Architecture:  x86_64 (amd64)  |   Type of failure:  Other
     Difficulty:  Unknown         |         Test Case:
     Blocked By:                  |          Blocking:
Related Tickets:                  |
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 (Sent by chrisreade at mac.com )
 Compiler giving up with simplifier ticks exhausted.
 Large amount of simplification may be going on to cause this.
 The problem goes away when using -fsimpl-tick-factor=1000 and the code
 runs.
 This is the session output without the flag (asking to have bug reported):

 chris$   ghc -O2 -rtsopts RedBlackStencilOpt.hs -v
 Glasgow Haskell Compiler, Version 7.6.3, stage 2 booted by GHC version
 7.4.2
 Using binary package database:
 /Library/Frameworks/GHC.framework/Versions/7.6.3-x86_64/usr/lib/ghc-7.6.3/package.conf.d/package.cache
 Using binary package database:
 /Users/chris/.ghc/x86_64-darwin-7.6.3/package.conf.d/package.cache
 hiding package binary-0.5.1.1 to avoid conflict with later version
 binary-0.6.4.0
 hiding package Cabal-1.16.0 to avoid conflict with later version
 Cabal-1.18.1.1
 wired-in package ghc-prim mapped to ghc-
 prim-0.3.0.0-d5221a8c8a269b66ab9a07bdc23317dd
 wired-in package integer-gmp mapped to integer-
 gmp-0.5.0.0-2f15426f5b53fe4c6490832f9b20d8d7
 wired-in package base mapped to
 base-4.6.0.1-6c351d70a24d3e96f315cba68f3acf57
 wired-in package rts mapped to builtin_rts
 wired-in package template-haskell mapped to template-
 haskell-2.8.0.0-c2c1b21dbbb37ace4b7dc26c966ec664
 wired-in package dph-seq not found.
 wired-in package dph-par not found.
 Hsc static flags: -static
 *** Chasing dependencies:
 Chasing modules from: *RedBlackStencilOpt.hs
 Stable obj: []
 Stable BCO: []
 Ready for upsweep
   [NONREC
       ModSummary {
          ms_hs_date = 2013-12-13 13:12:37 UTC
          ms_mod = main:RedBlackStencilOpt,
          ms_textual_imps = [import (implicit) Prelude,
                             import Data.Array.Repa.Stencil.Dim2 as A,
                             import Data.Array.Repa.Stencil as A, import
 Data.Array.Repa as A]
          ms_srcimps = []
       }]
 *** Deleting temp files:
 Deleting:
 compile: input file RedBlackStencilOpt.hs
 Created temporary directory:
 /var/folders/dz/m1mks1yn1bsft72zgh105sw40000gn/T/ghc93155_0
 *** Checking old interface for main:RedBlackStencilOpt:
 [1 of 1] Compiling RedBlackStencilOpt ( RedBlackStencilOpt.hs,
 RedBlackStencilOpt.o )
 *** Parser:
 *** Renamer/typechecker:
 *** Simplify:
 *** CorePrep:
 *** ByteCodeGen:
 Loading package ghc-prim ... linking ... done.
 Loading package integer-gmp ... linking ... done.
 *** gcc:
 '/usr/bin/gcc' '-m64' '-fno-stack-protector' '-m64'
 '-L/Library/Frameworks/GHC.framework/Versions/7.6.3-x86_64/usr/lib/ghc-7.6.3/base-4.6.0.1'
 '--print-file-name' 'libiconv.dylib'
 Loading package base ... linking ... done.
 Loading package pretty-1.1.1.0 ... linking ... done.
 Loading package array-0.4.0.1 ... linking ... done.
 Loading package deepseq-1.3.0.1 ... linking ... done.
 Loading package containers-0.5.0.0 ... linking ... done.
 Loading package old-locale-1.0.0.5 ... linking ... done.
 Loading package time-1.4.0.1 ... linking ... done.
 Loading package random-1.0.1.1 ... linking ... done.
 Loading package template-haskell ... linking ... done.
 Loading package QuickCheck-2.6 ... linking ... done.
 Loading package bytestring-0.10.0.2 ... linking ... done.
 Loading package primitive-0.5.0.1 ... linking ... done.
 Loading package vector-0.10.0.1 ... linking ... done.
 Loading package repa-3.2.3.3 ... linking ... done.
 *** Simplify:
 *** CorePrep:
 *** ByteCodeGen:
 *** Desugar:
 Result size of Desugar (after optimization)
   = {terms: 900, types: 1,810, coercions: 340}
 *** Simplifier:
 Result size of Simplifier iteration=1
   = {terms: 834, types: 1,757, coercions: 567}
 Result size of Simplifier iteration=2
   = {terms: 830, types: 1,721, coercions: 567}
 Result size of Simplifier
   = {terms: 830, types: 1,721, coercions: 567}
 *** Specialise:
 Result size of Specialise
   = {terms: 830, types: 1,721, coercions: 567}
 *** Float out(FOS {Lam = Just 0, Consts = True, PAPs = False}):
 Result size of Float out(FOS {Lam = Just 0,
                               Consts = True,
                               PAPs = False})
   = {terms: 993, types: 2,131, coercions: 567}
 *** Float inwards:
 Result size of Float inwards
   = {terms: 993, types: 2,131, coercions: 567}
 *** Simplifier:
 *** Deleting temp files:
 Deleting:
 /var/folders/dz/m1mks1yn1bsft72zgh105sw40000gn/T/ghc93155_0/ghc93155_0.s
 Warning: deleting non-existent
 /var/folders/dz/m1mks1yn1bsft72zgh105sw40000gn/T/ghc93155_0/ghc93155_0.s
 *** Deleting temp dirs:
 Deleting: /var/folders/dz/m1mks1yn1bsft72zgh105sw40000gn/T/ghc93155_0
 ghc: panic! (the 'impossible' happened)
   (GHC version 7.6.3 for x86_64-apple-darwin):
         Simplifier ticks exhausted
     When trying RuleFired Class op szipWith
     To increase the limit, use -fsimpl-tick-factor=N (default 100)
     If you need to do this, let GHC HQ know, and what factor you needed
     To see detailed counts use -ddump-simpl-stats
     Total ticks: 60402

 Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8613>
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