This issue was originally filed by perrys...@gmail.com

What steps will reproduce the problem?

Not exactly sure what in here is causing the error. I tried to break it down further but even taking out the '_two' seemed to resolve the malloc issue so I just extracted and reproduced the offending pattern with simple classes and unit test.

main() {
  test('temp', () {
    Thing.wrapper()();
  });
}

class Foo {
  final bool _one;
  final int _two;

  const Foo._(this._one, this._two);

  static final dynamic ctor = () {
    return new Foo._(true, 10);
  };
}
class Thing {
  static final dynamic wrapper = () {
    return () {
      other(null, values: null);
    };
  };

  static final dynamic other = (Action foo, [Foo values]) {
    if(values == null) { values = Foo.ctor(); }
  };
}

What is the expected output? What do you see instead?

Thinking that a malloc isn't the level of error I should be seeing in the editor :)

unittest-suite-wait-for-done
dart(6922,0xb0185000) malloc: *** error for object 0xb0183414: pointer being freed was not allocated
*** set a breakpoint in malloc_error_break to debug

What version of the product are you using? On what operating system?

Mac OSX Mountain Lion
Dart Editor version 0.4.3_r20602
Dart SDK version 0.4.3.5_r20602

Please provide any additional information below.