os::parseCmdLine fails on multiline strings

Input Source #2

import os, macros

macro huh (cmd1, cmd2: expr) : stmt =
  let cs = toStrLit(callsite ()) 
  echo "entering ", cs
  echo parseCmdLine ($cmd1)
  var a = $cmd2
  echo a
  echo "leaving ", cs, "\n"
  discard

macro huh2 () : stmt =
  let cs = toStrLit(callsite ()) 
  echo "entering ", cs 
  echo parseCmdLine ("""1 2 3""")
  echo "leaving ", cs, "\n"
  discard

macro huh3 () : stmt =
  let cs = toStrLit(callsite ()) 
  echo "entering ", cs 
  echo parseCmdLine ("""
    one
    two
    three
  """)
  echo "leaving ", cs, "\n"
  discard


huh "4 5", dog

huh2

huh3

output #2

entering huh "4 5", dog
@[4, 5]
dog
leaving huh "4 5", dog

entering huh2
@[1, 2, 3]
leaving huh2

entering huh3
stack trace: (most recent call last)
cmd.nim(22)              huh3
lib/nimrod/pure/os.nim(1450) parseCmdLine
lib/nimrod/pure/os.nim(1450, 10) Error: interpretation requires too many iterations