[GHC] #2124: My program compiles with -O1 but compiler panics with -O2 and up

[GHC]

#2124: My program compiles with -O1 but compiler panics with -O2 and up
--------------------------+-------------------------------------------------
 Reporter:  brassel       |          Owner:         
     Type:  bug           |         Status:  new    
 Priority:  normal        |      Milestone:         
Component:  Compiler      |        Version:  6.8.2  
 Severity:  minor         |     Resolution:         
 Keywords:  optimization  |     Difficulty:  Unknown
 Testcase:                |   Architecture:  x86    
       Os:  Linux         |  
--------------------------+-------------------------------------------------
Comment (by brassel):

 Ha, I succeeded in isolating the bug quite a bit:

 {{{

 module CompileBug where

 import qualified Data.Map as FM

 data J = J (String,String)

 myFromList = FM.fromList
 myLookup = FM.lookup
 myMember = FM.member

 elimConsts = myMember True

 makeTypeMap ps s = maybe undefined id (myLookup s fm)
   where
     fm = myFromList (concatMap typeMapTypeDecl ps)

 typeMapTypeDecl consDecls = zip (map (\ (J name) -> name) consDecls)
 undefined

 }}}

 Hope this helps!

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2124#comment:3>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler