Incorrect PYTHONPATH on Ubuntu 10.04

[smits]

Hi all,

I'm trying to use catkin on an older Ubuntu version due to legacy reasons. I've installed python2.7 on it from ppa:fkrull/deadsnakes and made sure I have CMake 2.8.3. I'm using virtualenv to make sure that catkin uses python2.7 since all catkin shebangs are without python version. Although it seems catkin is building ok the generated _setup_util.py exports the wrong PYTHONPATH:

grep PYTHONPATH /opt/ros/hydro/_setup_util.py

        'PYTHONPATH': 'lib/python./site-packages

For some reason the MAJOR and MINOR versions are empty. I've skimmed through the catkin sources but cannot find where this CMake variables get set.

[dirk-thomas]

The template used for the _setup_util.py file uses the CMake variable PYTHON_INSTALL_DIR (see

catkin/cmake/templates/_setup_util.py.in

Line 58 in 9a5da56

'PYTHONPATH': '@PYTHON_INSTALL_DIR@',

).

This CMake variable is computed in

catkin/cmake/python.cmake

Line 53 in 9a5da56

set(PYTHON_INSTALL_DIR lib/python${_PYTHON_PATH_VERSION_SUFFIX}/${PYTHON_PACKAGES_DIR}

but you should see a message during the configure step which states the Python version being used (

catkin/cmake/python.cmake

Line 27 in 9a5da56

message(STATUS "Python version: ${PYTHON_VERSION_MAJOR}.${PYTHON_VERSION_MINOR}")

).

There is a second code path for the tools catkin_make / catkin_make_isolated in Python. May be you can add some debug out there if the CMake part is not responsible:

catkin/python/catkin/builder.py

Line 238 in 9a5da56

def get_python_install_dir():

[wyc]

Please see #636

[smits]

The patch provided in #636 fixes my issue!

[dirk-thomas]

@smits Could you please provide some information after trying it on your machine why the Python version was not extracted for you? I think it would still be valuable to understand why it failed in the first place - e.g. the proposed patch relies on invoking Python which is performance wise always something to reconsider.

[dirk-thomas]

@smits See previous comment.

[smits]

Update: I was using indigo-devel instead of groovy-devel. With the original groovy-devel my issue is resolved even without #636

[dirk-thomas]

Thank you for clarifying the reason why this happened for you.