"not nil" checking is not working with object construction expression.

[kvinwang]

type
    PipeOrNil = ref object
    Pipe = PipeOrNil not nil

    ProcessOrNil = ref object
        stdin: Pipe
    Process = ProcessOrNil not nil

let a: PipeOrNil = nil
let b = Process(stdin: a) # expect compile error here, but it compiles ok


proc newProcess(stdin: Pipe): Process =
    Process(stdin: stdin)

let c = newProcess(a)  # works fine this way

[Araq]

Still an issue.