Regression: Pattern synonyms make GHCi 8.0.1 crash
This code:
{-# LANGUAGE PatternSynonyms #-}
data T = C
pattern P :: T
pattern P = C
pattern P' :: T
pattern P' = P
compiles fine with both GHC 7.10.3 and 8.0.1. However, if you try to load it into GHCi 8.0.1, it panics:
GHCi, version 8.0.1: http://www.haskell.org/ghc/ :? for help
Prelude> :l M.hs
[1 of 1] Compiling Main ( M.hs, interpreted )
ghc: panic! (the 'impossible' happened)
(GHC version 8.0.1 for x86_64-unknown-linux):
kindPrimRep.go rep_a18a
Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug
GHCi 7.10.3 does not crash, therefore it's a regression:
GHCi, version 7.10.3: http://www.haskell.org/ghc/ :? for help
Prelude> :l M.hs
[1 of 1] Compiling Main ( M.hs, interpreted )
Ok, modules loaded: Main.
*Main>
Trac metadata
Trac field | Value |
---|---|
Version | 8.0.1 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | GHCi |
Test case | https://gist.githubusercontent.com/int-index/17dfb68fd97f724aef2849d0defae0d6/raw/3dab71756bbafa197b93170310ccabfea8c92120/M.hs |
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