[CMake] cmake end user vs. developer rpath handling

[DIXON, MARK C.]

Hi,

I install lots of software packages under Linux and, increasingly, they 
use cmake instead of other methods (congratulations!)

Frustratingly for me, I seem to keep ending up in a fight with the various 
developer's cmake config files over what rpath should be set, among other 
things. Obviously, I think I know best, so would like to know how to win 
please :)

Sometimes, this does the trick. When it does, I'm very happy:

   cmake -D CMAKE_INSTALL_RPATH="/my/rpath" source_dir

I'm currently looking at a package 
(https://github.com/PointCloudLibrary/pcl) where this has no bearing on 
the rpath of the installed software - I seem to get something set by the 
developer.

Is there a way to reliably add to, or at least override, the developer's 
rpath in any cmake-built software?

Thanks,

Mark