id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
5703	vector fails to compile due to simplifier ticks exhausted	tibbe		"I thought the limit was raised in 7.4 but vector still fails to compile using the current ghc-7.4 branch:

{{{
Configuring vector-algorithms-0.5.3...
Preprocessing library vector-algorithms-0.5.3...
Building vector-algorithms-0.5.3...
[1 of 9] Compiling Data.Vector.Algorithms.Common ( Data/Vector/Algorithms/Common.hs, dist/build/Data/Vector/Algorithms/Common.o )
[2 of 9] Compiling Data.Vector.Algorithms.Radix ( Data/Vector/Algorithms/Radix.hs, dist/build/Data/Vector/Algorithms/Radix.o )
[3 of 9] Compiling Data.Vector.Algorithms.Search ( Data/Vector/Algorithms/Search.hs, dist/build/Data/Vector/Algorithms/Search.o )
[4 of 9] Compiling Data.Vector.Algorithms.Optimal ( Data/Vector/Algorithms/Optimal.hs, dist/build/Data/Vector/Algorithms/Optimal.o )
[5 of 9] Compiling Data.Vector.Algorithms.Insertion ( Data/Vector/Algorithms/Insertion.hs, dist/build/Data/Vector/Algorithms/Insertion.o )
[6 of 9] Compiling Data.Vector.Algorithms.AmericanFlag ( Data/Vector/Algorithms/AmericanFlag.hs, dist/build/Data/Vector/Algorithms/AmericanFlag.o )
[7 of 9] Compiling Data.Vector.Algorithms.Heap ( Data/Vector/Algorithms/Heap.hs, dist/build/Data/Vector/Algorithms/Heap.o )
[8 of 9] Compiling Data.Vector.Algorithms.Intro ( Data/Vector/Algorithms/Intro.hs, dist/build/Data/Vector/Algorithms/Intro.o )
ghc-stage2: panic! (the 'impossible' happened)
  (GHC version 7.4.0.20111213 for x86_64-apple-darwin):
	Simplifier ticks exhausted
    When trying UnfoldingDone ( ghc-prim:GHC.Classes.||{v r1c} [gid] :: ghc-prim:GHC.Types.Bool{(w) tc 3c}
                                                                        -> ghc-prim:GHC.Types.Bool{(w) tc 3c}
                                                                        -> ghc-prim:GHC.Types.Bool{(w) tc 3c} )
    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: 46921

Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
}}}"	bug	closed	normal		Compiler	7.3	duplicate			Unknown/Multiple	Unknown/Multiple	None/Unknown