Levity polymorphism panic in GHCi
With current master
,
$ ghci
GHCi, version 8.1.20170126: http://www.haskell.org/ghc/ :? for help
Loaded GHCi configuration from /home/ben/.ghci
λ> import GHC.Exts
λ> :set -XTypeApplications -XMagicHash -XTypeInType
λ> data TypeRep (a :: k) = TypeRep
λ> let typeRepKind = undefined :: TypeRep (a :: k) -> TypeRep k
λ> let typeRep = undefined :: TypeRep (a :: k)
λ> let x = typeRepKind (typeRep @(Maybe Int#))
ghc: panic! (the 'impossible' happened)
(GHC version 8.1.20170126 for x86_64-unknown-linux):
isUnliftedType
forall (a :: TYPE q). a :: TYPE q
Call stack:
CallStack (from HasCallStack):
prettyCurrentCallStack, called at compiler/utils/Outputable.hs:1166:58 in ghc:Outputable
callStackDoc, called at compiler/utils/Outputable.hs:1170:37 in ghc:Outputable
pprPanic, called at compiler/types/Type.hs:1869:10 in ghc:Type
Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug
Trac metadata
Trac field | Value |
---|---|
Version | 8.0.1 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | high |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | goldfire |
Operating system | |
Architecture |