Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with QFlags<Qt::KeyboardModifier>(NoModifier)

[Tom Goddard]

Mac ARM ChimeraX is logging many warnings

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with QFlags<Qt::KeyboardModifier>(NoModifier)

in ticket #7393.

[Tom Goddard]

This Qt bug report suggests this is probably caused by some modifier key press in a Qt text entry

​https://bugreports.qt.io/browse/QTBUG-95471

It looks like virtual key 36 might be the HOME key looking at the Qt 5 windows key mapper source code.

​https://code.woboq.org/qt5/qtbase/src/plugins/platforms/windows/qwindowskeymapper.cpp.html

[Tom Goddard]

Virtual keys 1, 8, 9, 36, and 51 appear in the warning messages of #7393, corresponding to VK_LBUTTON, Backspace, Tab, Home, and 3 key in the qwindowskeymapper.cpp. These may not be the right mappings for Mac. Here are the Qt:Key_X values

​https://doc.qt.io/qt-6/qt.html

I should probably just try typing lots of weird keys in an entry field. It may only happen on the ARM Mac ChimeraX so try in that.

[Tom Goddard]

In this sequence of warnings from ticket #7393 they seemed to try every combination of modifier keys.

Actually all the instances of this warning lists all modifier key combinations.

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(NoModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(ShiftModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(ControlModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(ShiftModifier|ControlModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(AltModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(ShiftModifier|AltModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(ControlModifier|AltModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(ShiftModifier|ControlModifier|AltModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(MetaModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(ShiftModifier|MetaModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(ControlModifier|MetaModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(ShiftModifier|ControlModifier|MetaModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(AltModifier|MetaModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(ShiftModifier|AltModifier|MetaModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(ControlModifier|AltModifier|MetaModifier)  

Mismatch between Cocoa '\x0' and Carbon '\xd' for virtual key 36 with
QFlags<Qt::KeyboardModifier>(ShiftModifier|ControlModifier|AltModifier|MetaModifier)  

[Tom Goddard]

Here is the source code that is issuing the warning.

​https://code.woboq.org/qt6/qtbase/src/gui/platform/darwin/qapplekeymapper.mm.html#536

[Tom Goddard]

This bug also appears on Intel ChimeraX 1.4 on an Intel Mac, ticket #7397

[Tom Goddard]

This same warning was seen in April 2022 probably just after ChimeraX started using Qt 6.3.0, ticket #6710, and there are 6 tickets that contain the warning.

[Tom Goddard]

I tried pressing all manner of modifier keys and home, and other non alpha-numeric keys in command-line and help browser on M1 Mac and Intel Mac and never generated this warning. I guess the keys have to be typed to the right widget to get this error. Don't have any further ideas how to reproduce. In any case seems like a Qt bug.