Deriving MPTC panic: tcSplitTyConApp
Current GHC HEAD panics when trying to compile test drv020 (added by me):
$ compiler/stage1/ghc-inplace -no-recomp -c -fglasgow-exts testsuite/tests/ghc-regress/deriving/should_compile/drv020.hs
ghc-6.5: panic! (the 'impossible' happened)
(GHC version 6.5 for i386-apple-darwin):
tcSplitTyConApp
{main:ShouldSucceed.MonadState{tc rdb} base:GHC.Base.Int{(w) tc 3J}
<nt>main:ShouldSucceed.Foo{tc rat}}
It seems to have problems with this declaration:
newtype Foo a = MkFoo (State Int a)
deriving (Monad, MonadState Int)
Trac metadata
Trac field | Value |
---|---|
Version | 6.5 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | Unknown |
Architecture | Unknown |