panic: funArgTy
The following module crashes GHC 6.11.20090615:
module V where
import GHC.IO.Handle.Types
import GHC.IO.Handle.Internals
f :: Handle -> IO ()
f hdl = withHandle_ "" hdl $ \h -> return h{haDevice=undefined}
results:
$ ghc-testing2 --make V.hs
[1 of 1] Compiling V ( V.hs, V.o )
ghc-stage2: panic! (the 'impossible' happened)
(GHC version 6.11.20090615 for x86_64-unknown-linux):
funArgTy ghc-prim:GHC.Unit.(){(w) tc 40}
It imports some internals of the IO library; I tried to reproduce it with a completely standalone module, but failed. The field haDevice
of Handle__
has existential type - normally GHC rejects a record update when the field has existential type, but does not in this case, I'm not sure why.
Trac metadata
Trac field | Value |
---|---|
Version | 6.11 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler (Type checker) |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |