Take the following code:

class Foo: Object
{
  public int bar { get; set; }
  public void poo ()
  {
    bar = 3;
    _bar = 3; // BUG -Works even if not defined.
    // _boz = 3; // Raises an valac error as expected.
  }
}

void main ()
{
  var f = new Foo ();
  f.poo ();
}


this code works, even if _bar is not defined. The bug is that valac doesn't complain. gcc also doesn't complain, because there is the field for bar is prefixed with an "_" in the ccode.
An error is raised if e.g. _boz is used instead of _bar.

This happens in 0.14.0 (release) as well as in master.