Panic when using a type synonym
I'm getting the following "the impossible happened" error when trying to compile the code in the attachment:
[2 of 3] Compiling Data.Mod.FiniteRing ( Data/Mod/FiniteRing.hs, dist/build/Data/Mod/FiniteRing.o )
ghc: panic! (the 'impossible' happened)
(GHC version 7.4.1 for x86_64-unknown-linux):
tyThingTyCon
Data constructor `modular-0.1.0:Data.Mod.Types.FiniteRing{d r0}'This only happens when I use the Mod type synonym. When I spell the full GenMod type everything works fine. Also the first compilation run after a "cabal clean" works fine.
Steps to reproduce:
- Unpack the attached cabal package.
- Compile (cabal configure, cabal build).
- Touch Data/Mod/FiniteRing.hs.
- Compile again (cabal build).
Trac metadata
| Trac field | Value |
|---|---|
| Version | 7.4.1 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
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| Related | |
| Blocking | |
| CC | |
| Operating system | |
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