Windows 10, GeForce 780ti 3gb
Broken: 2.78 641e586, daily build 6/10 2016, same issue in official release 2.78
Short description of error
Experimental feature set
When linking modifiers with ctrl+l with a subsurf modifier on the active object that also has adaptive enabled the adaptive setting or dicing scale is not copied over to the other objects.
However if that object had a subsurf modifier previously that was removed with the adaptive enabled and a set dicing scale, that object will regain those settings if a new subsurf is linked.
Exact steps for others to reproduce the error
Set experimental feature set
duplicate the default cube
add subsurf modifier to one of the cubes
check the "adaptive" checkbox on the subsurf modifier
select the other cube and then with shift held down select the cube with the subsurf modifier so that it becomes the active object
press ctrl + l
on the now subdivided second cube, the adaptive won't be enabled.