[CMake] Linking archives in a sibling directory

[Raymond Wan]

Hi all,

I'm having a problem understanding how I can link to an archive in
another directory which is not a subdirectory. For example:

myproj
  +-- main
    +-- CMakeLists.txt
    +-- source files for main program
  +-- dir-A
    +-- CMakeLists.txt
    +-- source files for sub-program A
  +-- dir-B
    +-- CmakeLists.txt
    +-- source files for sub-program B


Basically, I would like to make a larger project (main) and I'm
building and testing each of its components separately.

Right now, the main's CMakeLists.txt looks something like this:


INCLUDE_DIRECTORIES (../dir-A)
SUBDIRS (../dir-A)
ADD_EXECUTABLE (main ${MAIN_SRCS})
TARGET_LINK_LIBRARIES (main subprogA_ar)


which works fine so far (the CMakeLists.txt in dir-A generates the
archive subprogA_ar).

However, I just found out that SUBDIRS is deprecated and so, replaced
it with "ADD_SUBDIRECTORY".  That's when I got an error about "dir-A"
not being a subdirectory.  Obviously, I was not using "SUBDIRS" before
as it was intended...  :-)

I've also tried adding "dir-A" as a LINK_DIRECTORIES with no success.
It is unable to find subprogA_ar.

I'm not sure if it is possible, but ideally, when I run "make" in
main/, I would like it to rebuild the targets in "dir-A" (including
the archive) and link that in.

I'm also open to the possibility that I got the above organization all
wrong and should have only one large CMakeLists.txt in a directory
structure like this:


myproj
  +-- main
    +-- CMakeLists.txt
    +-- source files for main program
    +-- dir-A
      +-- source files for sub-program A
    +-- dir-B
      +-- source files for sub-program B


Is this what I should have done??

Thank you!

Ray