"the `impossible' happened: Maybe.fromJust: Nothing" when using {-# SOURCE #-}

It is possible to use the {-# SOURCE #-} directive to make ghc crash. Attached is a program that does it with ghc 6.4.2. Here is a run of my compiler:

avatar@avatar:~/Docs/sandbox/haskell/hs-boot> make
ghc --make Main.hs
Chasing modules from: Main.hs
Compiling C                ( ./C.hs, ./C.o )
Compiling A                ( ./A.hs, ./A.o )
Compiling A[boot]          ( ./A.hs-boot, ./A.o-boot )
Compiling B                ( ./B.hs, ./B.o )
Compiling Main             ( Main.hs, Main.o )
Linking ...
ghc-6.4.2: panic! (the `impossible' happened, GHC version 6.4.2):
        Maybe.fromJust: Nothing

The bang seems to happen in

./compiler/main/DriverPipeline.hs:320:      linkables = map (fromJust.hm_linkable) home_mod_infos

though I'm not 100% sure.

Cheers,

Misha

Trac metadata

Trac field	Value
Version	6.4.2
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
Test case
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CC	avatar@hot.ee
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