Iirc with_kf5 comes implicitly through the optional dependency macro we use.

In D1439#26762, @nienhueser wrote:

Iirc with_kf5 comes implicitly through the optional dependency macro we use.

What "optional dependency macro", I did not get across that one?
hm, lxr.kde.org only shows this very line in Marble. And google in its search result on "with_kf5" Marble developers/packagers talking about it, and then something in Quassel which seems self-used var though. No
Any suggestions who could know more? I have never seen it in all my porting work so far :) (perhaps that was Qt4/Qt5-parallel build specific?).

I mean MACRO_OPTIONAL_FIND_PACKAGE from MarbleMacros.cmake. It has

option(WITH_${_name} "Search for ${_name} package" ON)
if (WITH_${_name})
   find_package(${_name} ${ARGN})
else (WITH_${_name})

and we call it like

macro_optional_find_package(KF5 ...