Code generation error while declaring and initializing a variable to 0

There is a major bug in code generation when a variable is declared and initialized to 0. In the example code below, “var foo: Integer := 0” is completely eliminated while older versions of DWS properly set foo to 0.

procedure TestBug;
var sum: Integer;
begin
  for var i:=0 to 3 do begin
    var foo: Integer := 0; //This is eliminated by the compiler!
    for var j:=0 to 3 do begin
      inc(foo);
      inc(sum,foo);
    end;
  end;
  WriteLn(sum);
end;

This works:

procedure TestBug;
var sum: Integer;
begin
  for var i:=0 to 3 do begin
    var foo: Integer;
    foo := 0;
    for var j:=0 to 3 do begin
      inc(foo);
      inc(sum,foo);
    end;
  end;
  WriteLn(sum);
end;

As well as this:

procedure TestBug;
var sum, foo: Integer;
begin
  for var i:=0 to 3 do begin
    foo := 0;
    for var j:=0 to 3 do begin
      inc(foo);
      inc(sum,foo);
    end;
  end;
  WriteLn(sum);
end;

This elimination is also done only if the variable is set to 0. For example, this is not eliminated by the compiler:

var foo: Integer := 1;

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