Reminder: When requiring ECM 5.85 or newer, be aware of KDE_COMPILERSETTINGS_LEVEL concept

[Friedrich W. H. Kossebau]

Hi,

((kde-core-devel as CC:, please reply only to kde-devel)

Time for a quick reminder after half a year, given this is not daily business 
but people might more & more require newer ECM and run into this.
Quoting the important bit below, for the full initial email, please see
    https://marc.info/?l=kde-devel&m=162893561025502&w=2


TL;DR
Starting with ECM 5.85 KDECompilerSettings will provide some stricter 
settings, which you can control on the toplevel by KDE_COMPILERSETTINGS_LEVEL 
and then again per settings category, for a stable set of settings matching 
your project requirements across ECM versions, not affected by the minimal 
required ECM version.
Make sure to include KDECompilerSettings right after find_package(ECM), before 
any other find_package() calls (best done in any case due to a current flaw).
While your minimum required ECM version is < 5.85, no other change is needed.
If you start to require newer minimum ECM >= 5.85, and do not want any newer 
stricter settings take effect for now, call
    set(KDE_COMPILERSETTINGS_LEVEL 5.84.0)
    include(KDECompilerSettings NO_POLICY_SCOPE)
Port any usage of KDEFrameworkCompilerSettings outside of KDE Frameworks 
modules to that once you can afford to require ECM >= 5.85.
For more, see docs on
    https://api.kde.org/ecm/kde-module/KDECompilerSettings.html

Cheers
Friedrich