[Flash] abstract on haxe.ds.Vector<T> confuses Vector with Int

[YellowAfterlife]

try.haxe | code:

import haxe.ds.Vector;
class Main {
    static function main() {
        new AbsVector<Int>(42);
    }
}

abstract AbsVector<T>(Vector<T>) {
    public function new(size:Int) {
        this = new Vector<T>(size);
        trace(this);
        trace(Std.is(this, Int));
        trace(this.length);
    }
}

outputs

Main.hx:11: 42
Main.hx:12: true
[Fault] exception, information=ReferenceError: Error #1069: Property length not found on Number and there is no default value.

which suggests that this = new Vector<T>(size) in the abstract's constructor somehow compiles into this = size.
What's going on?

[nadako]

Sounds like #4783

[Simn]

Right, I forgot about the Flash part of #4783. I know that using Vector with type parameters like that causes problems, but that error is still really strange.

[synek317]

It is even easier to reproduce without having to use abstract:
http://try.haxe.org/#6C006

How can it even happen?

[ncannasse]

Ah right, it seems that Vector<KTypeParam> is compiled as Object by genSWF, which is normal for type safety (because the vectors are not compatible between them) but should throw an error when used with new because we don't know which vector class to construct.

function construct : 
	   0 this
	   1 scope
	   2 findpropstrict Object
	   3 reg 1
	   4 true
	   5 constructproperty Object 2
	   6 cast Object
	   7 setreg 2
	   8 findprop xxx
	   9 reg 2
	  10 initprop xxx