Panic when loading file with nested pattern synonyms into ghci
The following code compiles fine for me in GHC 7.10.1, but fails in GHC 8.1.20160502
{-# LANGUAGE PatternSynonyms #-}
{-# LANGUAGE ViewPatterns #-}
data Foo a = Foo a a
pattern A a1 a2 = Foo a1 a2
pattern B a1 a2 = A a1 a2
The problem is the nested pattern. Compiling gives:
[1 of 1] Compiling Main ( Bug1.hs, interpreted )
ghc-stage2: panic! (the 'impossible' happened)
(GHC version 8.1.20160502 for x86_64-unknown-linux):
kindPrimRep.go rep_a85f
Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug
Trac metadata
Trac field | Value |
---|---|
Version | 7.10.3 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |