iOS: Significant memory pressure during recursive Dialog::exec() (multiple windows)

On iOS memory leak happens upon every Dialog::exec(). Attached is a sample program that just opens modal dialog. Every time the dialog is opened and closed a few MB (~9MB on iPhone, ~12MB on iPad, i.e. mem leak size depends on screen resolution) are added to the consumed memory (see attached screen shot from Xcode).
Run attached sample and just press upper button to open new dialog and then Close button.