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GHC 7.9 panics (simplifier ticks exhausted) on `half-0.2`

Compiling hackage:half-0.2 results in a GHC Panic:

$ ghc --version && ghc --print-project-git-commit-id
The Glorious Glasgow Haskell Compilation System, version 7.9.20141202
bf2d75417b5be7e8a79a26ee57a81e00682dabd4

$ cabal get half-0.2 && cd half-0.2/src/Numeric/
Unpacking to half-0.2/

$ ghc -Wall -O -fforce-recomp -c Half.hs 
ghc: panic! (the 'impossible' happened)
  (GHC version 7.9.20141202 for x86_64-unknown-linux):
	Simplifier ticks exhausted
  When trying UnfoldingDone lvl_s5yo
  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: 125160

Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
Trac metadata
Trac field Value
Version 7.9
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC ekmett
Operating system
Architecture
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