Ill-kinded value is not rejected immediately

The expression Just (1#) is ill-kinded, since Just expects a parameter of type a :: * not #. GHC 7.6.3 recognizes this

λ> :t Just (1#)

<interactive>:1:7:
    Couldn't match kind `*' against `#'
    Kind incompatibility when matching types:
      a0 :: *
      GHC.Prim.Int# :: #
    In the first argument of `Just', namely `(1#)'
    In the expression: Just (1#)

while HEAD gives

λ> :t Just (1#)
Just (1#) :: a ~ GHC.Prim.Int# => Maybe a

Not a big deal, attempting to do anything with this value gives the same error as in 7.6.3. But still, I think it should be rejected as ill-kinded at sight.

Trac metadata

Trac field	Value
Version	7.7
Type	Bug
TypeOfFailure	OtherFailure
Priority	low
Resolution	Unresolved
Component	Compiler (Type checker)
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture