Compiler Generates Broken Code for Anonymous Iterators

[Varriount]

Erroneous code is generated for generic, anonymous iterators:

proc count*[T](start: T, step = 1): auto =
  iterator counter: T {.closure.} =
    ## An iterator function that returns evenly spaced values of ordinal T,
    ## starting with `start`
    ## Note, this doesn't have any protections against overflow errors!
    ##
    ## Parameters:
    ##   start: A starting ordinal
    ##   step: The space between returned values.
    var i = start
    if step < 0:
      while True:
        dec(i, step)
        yield i
    if step > 0:
      while True:
        inc(i, step)
        yield i

  return counter

[Varriount]

This issue can be closed now that closure iterators are fixed (it now works on win64 and win32)