[QT 5.9.7][Linux X11]Different behavior QMenu on Debug and Release build.

[kas_ru]

I have simple code with QMenu class:

QMenu* menu = new QMenu( mainWindow_ )
menu->setSizePolicy( QSizePolicy::Preferred, menu->sizePolicy().verticalPolicy() );
menu->setFixedWidth( QWIDGETSIZE_MAX );
menu->clear();

QAction* action;

action = menu->addAction( tr( "Send report" ) );
action->setObjectName( "sendReport" );

action = menu->addAction( tr( "Show in folder" ) );
action->setObjectName( "showInFolder" );
menu->setSizePolicy( QSizePolicy::Fixed, menu->sizePolicy().verticalPolicy() );
menu->setFixedWidth( rect["width"].toInt() );

QSize screenSize = QApplication::desktop()->screenGeometry().size();
QPoint pos = mapToGlobal( QPoint( rect["x"].toInt(), rect["y"].toInt() + rect["height"].toInt() ) );
menu->popup( pos );
if( pos.y() + menu->height() > screenSize.height() )
{
     menu->move( mapToGlobal( QPoint( rect["x"].toInt(), rect["y"].toInt() - menu->height() ) ) );
}
action = menu->exec();
if( action )
{
     if( action->objectName() == "sendReport" )
     {
          OnSendReportTriggered();
     }
     else if( action->objectName() == "showInFolder" )
     {
          OnShowInFolderTriggered();
     }
}

Qt 5.9.7 build from source with Debug and Release variant.
On Debug variant QMenu after call menu->exec() does show correct.
On Release variant QMenu after call menu->exec() always return 0 (menu don't show).

Build system on Debian and Ubuntu, try compilers: gcc5, gcc6, gcc7, clang6, clang7.
Please help. What the problem?

[aha_1980]

@kas_ru Please don't cross-post. Closing this one as duplicate of https://forum.qt.io/topic/99039/qt-5-9-7-linux-x11-different-behavior-qmenu-on-debug-and-release-build