[CMake] Object targets and link libraries

[Daniel Wirtz]

Hey all,

i've been wondering why CMake (3.3.+) yells at me if i want to add link 
libraries to an OBJECT target.
Consider the scenario

find_package(package_with_bar_target)

add_library(foo OBJECT ${foo_src})

# Would like to write

# target_link_libraries(foo bar)

# But have to use

target_include_directories(foo PRIVATE $<TARGET_PROPERTY:bar,INTERFACE_INCLUDE_DIRECTORIES>)


I know that intuitively "link library" is something different than 
"include directory". but one of the nice things
of cmake is that it automatically sorts out everything for you when you 
specify link libraries.
if there are more bar-dependent properties that need to be set in order 
to successfully compile foo (e.g. compile flags),
i have to literally re-write all the nice internal cmake logic to 
establish the compile environment of bar for foo.

what's the plan with that? or are there any other (less involved) 
solutions? i need the objects of foo inside a larger
target and want to avoid having a separate library being build that 
needs extra linking.

cheers!

-- 
Dr. Daniel Wirtz
Dipl. Math. Dipl. Inf.
SRC SimTech
Pfaffenwaldring 5a
+49 711 685 60044