Compiler crash on invalid type class instance

If you try compiling the following code, the compiler crashes

class Foo a where
    foo :: a -> ()

class Bar a where
    bar :: a -> ()

instance (Foo a) => (Bar a -> ()) where
    bar = undefined

*** Exception: compiler/rename/RnSource.lhs:430:14-81: Irrefutable pattern failed for pattern Data.Maybe.Just (inst_tyvars,
                                                        _,
                                                        SrcLoc.L _ cls,
                                                        _)

Trac metadata

Trac field	Value
Version	7.4.2
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture