[sysadmin/release-tools/frameworks/5.0] /: KF5: auto-increase QT_DISABLE_DEPRECATED_BEFORE when upgrading the min Qt version

[Friedrich W. H. Kossebau]

Am Donnerstag, 24. Oktober 2019, 22:16:47 CEST schrieb David Faure:
> Git commit fb4639b0b5f2a51d124949d59b9a327bf66c8f04 by David Faure.
> Committed on 24/10/2019 at 20:15.
> Pushed by dfaure into branch 'frameworks/5.0'.
> 
> KF5: auto-increase QT_DISABLE_DEPRECATED_BEFORE when upgrading the min Qt
> version

BTW, we want to also set
    -DQT_DEPRECATED_WARNINGS_SINCE=0x060000
otherwise the deprecations done with QT_DEPRECATED_VERSION in Qt's API will 
not emit warnings, because QT_DEPRECATED_WARNINGS_SINCE defaults to 
QT_DISABLE_DEPRECATED_BEFORE if set.
Cmp. https://code.woboq.org/qt5/qtbase/src/corelib/global/qglobal.h.html#310 
ff.

Otherwise there will be bad surprises when bumping 
QT_DISABLE_DEPRECATED_BEFORE.

Cheers
Friedrich