Simplify CMake Options

[markus2330]

Many build combinations are currently broken:
http://build.libelektra.org:8080/job/elektra-multiconfig-gcc47-cmake-options/

There are 8192 possible cmake flag combinations even though many of those do not make sense. E.g. BUILD_PDF only makes sense if BUILD_DOCUMENTATION is active and ENABLE_TESTING only makes sense if BUILD_TESTING is active.

Concrete suggestion how we can reduce flags can be suggested here.

use enum instead of the boolean flags above

Unrelated to the issue, but to improve consistency we will also introduce a BINDINGS cmake variable that works like PLUGINS and TOOLS.

[manuelm]

Please first merge #104 before introducing new build flags or variables

[markus2330]

@manuelm Thank you for reminding me.
Another issue we already discussed is that testcases do not work with BUILD_SHARED. Thats also a class of combinations where the builds fail. It would be nice to find a solution for that, too. (maybe just collecting all directories of plugins with add_plugins and adding it to LD_LIBRARY_PATH is enough)

[manuelm]

On my development vm I don't build statically as this just increases build time. Instead I've created a small script which searches for all shared objects below $build/src/plugins and symlinks them into a libs directory. This way I don't have a massive list in LD_LIBRARY_PATH

[markus2330]

The buildtime is not increased anymore when add_plugin is used. (It will be compiled once and linked 3 times)

Currently without full+static no tests how build, have you changed CMake for that what you describe?

Maybe setting CMAKE_LIBRARY_OUTPUT_DIRECTORY and CMAKE_RUNTIME_OUTPUT_DIRECTORY in cmake is enough (+ setting LD_LIBRARY_PATH to it)

[manuelm]

No, didn't change anything.

What I wanted to say is that symlinking the plugins is probably easier and more manageable than building a huge list. Also the bindings already need to modify the library path for their tests so please take this into account.

[markus2330]

I think the commit is already the solution, using OUTPUT_DIRECTORY the executables using the shared libs+plugins seem to just work. (Of course now the ifs for linking the correct thing is needed everywhere, a cmake function should be able to do it at one place)

[markus2330]

Lots of progress, see http://build.markus-raab.org:8080/job/elektra-multiconfig-gcc47-cmake-options/

BINDINGS is introduced and works nicely

still open is BUILD_PDF, but thats a minor issue, and documentation of CMake flags should be improved

[markus2330]

No real reason to break existing packages by changing BUILD_PDF, so I will close this for now.