[CMake] Undesirable behavior of TARGET_LINK_LIBRARIES()

[Brad King]

Darrin West wrote:
>  
> 
> It seems to me that TARGET_LINK_LIBRARIES and ADD_DEPENDENCIES are 
> “poorly” defined, and lead to problems. I think the fix is “easy”, but 
> might not be popular.
> 
>  
> 
> My comments might be related to the following question in the FAQ:
> 
> http://www.cmake.org/Wiki/CMake_FAQ#Why_are_libraries_linked_to_my_shared_library_included_when_something_links_to_it.3F

Note the last line in that answer about the future separation of 
interface link rules from implementation link rules.  We are actually 
pretty close to implementing that.  Basically one will be able to write 
something like

   add_library(mysharedlib SHARED ...)
   target_link_libraries(mysharedlib myhelperlib)
   set_target_properties(mysharedlib PROPERTIES
     INTERFACE_LINK_LIBRARIES ""
     )

and then linking to mysharedlib will not chain to any libraries.  The 
INTERFACE_LINK_LIBRARIES property will list the libs to be linked when 
mysharedlib is linked.  There will be no chaining.  For compatibility 
the old behavior will be preserved if the property is not set.

-Brad