Correct way to set target include directory property ?

[Alexander Neundorf]

On Thursday 18 July 2013, Stephen Kelly wrote:
> Alexander Neundorf wrote:
> > Hi,
> > 
> > I just made kconfigwidgets build also standalone[1].
> > 
> > It didn't work immediately, since it didn't have the correct include dirs
> > set. As I understand it, they should come from the KWidgetsAddons and
> > KConfig libraries it links against, but those do not yet set them.
> > 
> > Attached is what I committed to set the include directory properties for
> > those libraries.
> > Is this the correct way to do it or is there a better way ?
> 
> There is, yes.
> 
> See the install-interface-includes branch in next. We can make it part of
> INSTALL_TARGETS_DEFAULT_ARGS when we depend on CMake 2.8.12.

Ah, that one.
Still, is there a reason that the directory used in 
target_include_directories(KConfigCore
   INTERFACE "$<INSTALL_INTERFACE:${INCLUDE_INSTALL_DIR}>" )

must be an absolute path ?
Or has this also already been changed in cmake master/nexts, so that it adds 
${CMAKE_INSTALL_PREFIX} if it's a relative path ?

Alex