so we can use exported targets like "Python3::Python", which is defined
only if CMAKE_ROLE is "PROJECT". but this global property was introduced
by CMake 3.14, but the minimum required version of CMake is 3.10.2 in
Ceph project at this moment. let's set it if it's not defined.
Signed-off-by: Kefu Chai <kchai@redhat.com>
use the ones shiped from the latest cmake. which
* enables us to find the recent python intepreter and development files,
* find intepreter and development in a single `find_pacakge()` command,
simpler this way and less error prone.
and to accomodate this change:
* all `PYTHON${PYTHON_VERSION}_*` variables are renamed to
`Python${PYTHON_VERSION}_*` if we use `find_package(Python2...)` or
`find_package(Python3...)` to find python2 or python3 instead of using
`find_package(Python...)`.
* use "2" explicitly when using python2, as `Python_*` variables are not
defined anymore
* when compiling python support of ceph-mgr, continue using `Python_*`
variables. because we find the python interpreter and development
files using `find_pacakge(Python...)` for ceph-mgr.
Signed-off-by: Kefu Chai <kchai@redhat.com>
