Includes (was: Re: KF6 meeting notes 2022-01-04)

[Friedrich W. H. Kossebau]

Am Dienstag, 4. Januar 2022, 18:07:45 CET schrieb Volker Krause:
> - in some places includes with the framework prefix don't seem to work
> anymore (ie. <KFramework/KBla> vs <KBla>), any idea where those extra
> include directories came from/got lost?

FTR, pointed on irc to some insights about design of include folder layout 
noted in an older comment here:
https://invent.kde.org/pim/akonadi/-/merge_requests/70#note_300273

And follow-up on what makes path relative to "include/KF5" work:
https://invent.kde.org/pim/akonadi/-/merge_requests/70#note_300304

Seems at least the version files as currently installed do not match the 
pattern as described above, but that might have been just a mistake which 
happened to work, so no-one noticed.
Installing kfoo_version.h instead of to include/KF5 to include/KF5/KFoo should 
still work as before., at least for anything which reads include paths from 
installed metadata like cmake config files, pkgconfig files or qmake pri 
files.

The currently by KF5 modules provided pkgconfig files or qmake pri files seem 
to even never add "include/KF5" in the samples I looked at, so any #include 
<kfoo_version.h> would have never worked with them.

So I would propose to fix things and adapt the version files to be installed 
into the module prefix now already. Any serious project should get the include 
paths from the build metadata and not try to heuristically find version 
headers and try to heuristically detect the version from that.

Cheeers
Friedrich