Q_ENUMS cannot use LLONG_MAX

[jmlich]

The Q_ENUMS is deprecated and it is advised to use Q_ENUM see https://doc.qt.io/qt-6/qobject-obsolete.html#Q_ENUMS

The Q_ENUM explicitly says that enum is stored as signed int. See https://doc.qt.io/qt-6/qobject.html#Q_ENUM

In the end the InvalidValue64 = LLONG_MAX assignment causes that whole enum type long long, which is not allowed in Qt. I was thinking that this is probably Qt bug, but it is actually feature https://bugreports.qt.io/browse/QTBUG-119620

It leads to strange compilation error in Qt 6.6 (maybe even 6.5). See attached build.log. I am not sure if this solution is good or wise, but I hope it will work until we will find better solution.

[pvuorela]

I wonder why such a special 64-bit enum value even exists. Not spotting even usage immediately.

@mlehtima your addition, maybe you have some idea. Could we just use one enum with same value everywhere?

Addition: wonder how such should an enum value even be used. "if (someValue == Invalid || someValue == Invalid64)" or ifdeffing based on bitness? Both would feel ugly.

[monich]

how about this:

qofonoextcell.h

    static const int InvalidValue;
    static const qint64 InvalidValue64;

qofonoextcell.cpp

const int QOfonoExtCell::InvalidValue = INT_MAX;
const qint64 QOfonoExtCell::InvalidValue64 = LLONG_MAX;

[pvuorela]

how about this:
[...]

Maybe that's slightly better but still seems unusable for the client of this api. Those shouldn't need to care about the bitness of the system.

I'd say either

• Kill InvalidValue64 somehow and define just one invalid value, or
• Where applicable here, replace the property types int -> QVariant and use invalid variant for the "doesn't exist" case.

[monich]

Ah, forget what I proposed, those constants are exposed to QML, they have to remain what they are, to avoid breaking the API.

[pvuorela]

Ah, forget what I proposed, those constants are exposed to QML, they have to remain what they are, to avoid breaking the API.

Still repeating what I've been saying, don't expect anyone really using Invalid64 from QML as such bitness cannot even use c/c++ ifdes. Code would need to always compare if it's either of the invalids. That and this being an non-public component and Invalid64 never included in a sailfish release so far. At least that has to go.

[pvuorela]

Correcting myself: on closer look the Invalid64 doesn't seem to be about bitness of the system but bitness of the property, i.e. nci being qint64. But that's still not too good api since developer would need to pay close attention on how invalidness of each value is checked.

For another thing, not immediately sure how well that property works in qml as 64 bit properties have been problematic there. Didn't test.

Haven't spotted usage for that either so far.

[mlehtima]

As mentioned by @pvuorela that enum has never reached any Sailfish OS release and it is highly unlikely that anyone would have used the enum so I think it would be fine to remove the broken unusable code.

[pvuorela]

Switched the type to string to allow qml usage.

And as commented on the other PR, noticed while playing that none of the properties work nice in QML as the values cannot be compared directly to invalid value due to javascript float numbers.