Loop/errors on tallying

This loops

let x :  (Int -> Int) & ('b -> 'b) & (('a -> 'a) -> ('a -> 'a)) = fun (x : 'd ) : ('d) = x : ('d) ;;

This gives the wrong result

# let x : (('a -> 'a) -> ('a -> 'a)) & (Int -> Int) & ('d -> 'd) = fun (x : 'd ) : ('d) = x : ('d) ;;
This expression should have type:
'd -> 'd
but its inferred type is:
(('a -> 'a) -> 'a -> 'a) & (Int -> Int) & ('d -> 'd)

while each separate intersection works:

# let x : (('a -> 'a) -> ('a -> 'a)) & (Int -> Int)  = fun (x : 'd ) : ('d) = x : ('d) ;;
val x : (Int -> Int) & (('a -> 'a) -> 'a -> 'a) = 
# let x : ('d -> 'd) = fun (x : 'd ) : ('d) = x : ('d) ;;
val x : 'd -> 'd =