[GHC] #3118: ghc: panic! (the 'impossible' happened): Missing alternative

[GHC]

#3118: ghc: panic! (the 'impossible' happened): Missing alternative
--------------------+-------------------------------------------------------
Reporter:  calvins  |          Owner:                
    Type:  bug      |         Status:  new           
Priority:  normal   |      Component:  Compiler      
 Version:  6.10.1   |       Severity:  normal        
Keywords:           |       Testcase:                
      Os:  Linux    |   Architecture:  x86_64 (amd64)
--------------------+-------------------------------------------------------
 When I include the -auto-all option (in addition to -prof) on the entry
 for Main in my Cabal file, I get the ghc panic message below. Full compile
 output attached.


 {{{
 [10 of 10] Compiling Main             ( Rdf4hParseMain.hs,
 dist/build/rdf4h/rdf4h-tmp/Main.o )
 ghc: panic! (the 'impossible' happened)
   (GHC version 6.10.1 for x86_64-unknown-linux):
         Missing alternative
     main:Main.OutputFormat{d r16LZ}
     (main:Main.Help{d r16M9}, [], lvl_s17ar{v} [lid])
     (main:Main.Debug{d r16M7}, [], lvl_s17as{v} [lid])
     (main:Main.Version{d r16M5}, [], lvl_s17at{v} [lid])

 }}}

 To reproduce the bug, check out a tagged version of the code using:

 darcs get -t 'ghc bug report' http://protempore.net/rdf4h

 And then edit the cabal file by adding "-prof -auto-all" to the library
 and main entries, and you should see what I see above if it's
 reproducible. It compiles fine if the options are only added to the
 library block, and it compiles fine if '-prof' but not '-auto-all' is
 added to the executable block, but fails when '-prof' and '-auto-all' are
 both added to the executable block.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3118>
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