Failing to add optional dependencies!
Hello,
I have 3 ros packages: A, B and C
B depends on A (as a required dependency) and C depends on A & B (but both as optional dependencies)
I want to make the building of C always work, whether A or B both exist, both do not exist, or one of them exists without the other.
In package C, I have written the CMakeLists.txt to first search for A, and if found also search for B:
find_package(catkin COMPONENTS
A
)
if (${A_FOUND})
find_package(catkin COMPONENTS
B
)
if (${B_FOUND})
add_definitions(-DFLAG)
endif(${B_FOUND})
endif(${A_FOUND})
In package.xml, I had to add B as a dependency for it to look for A and B at all
What I get is that C is building in all cases except when B exists but A doesn't
Please any explanation or help??
I am not sure why you want to do this, but: If B depends on A, B requires A and thus B should not work/exist if A is not there. Is this the problem?
Note that -- in CMake, not just Catkin -- multiple
find_package(..)s for the same package will not work as you expect: depending on how the find script is written, they might return early (if they don't consider theCOMPONENTSarg), or overwrite each other. I would not use ....
find_package(catkin COMPONENTS ..), but just do afind_package(A),find_package(B), etc. The only thing thefind_package(catkin COMPONENTS ..)does for you is gather all include/lib flags for you and let you do${catkin_LIBRARIES}instead of having to list everything individually.@mig: If A is not there, B should not build. That's fine... My issue is that C is not building too!
@gvdhoorn: even with
find_package(A)andfind_package(B), it also fails... If callingfind_package(...)several times is not the way to do this, do you suggest something else?what fails?
find_package(..)is fine, you just don't want to call the same find/config script multiple times, or be very careful about it.