g2o::csparse_extension link errors

[matlabbe]

../../../bin/librtabmap_core.so.0.11.2: undefined reference to `g2o::csparse_extension::cs_cholsolsymb(cs_sparse const*, double*, cs_symbolic const*, double*, int*)'
../../../bin/librtabmap_core.so.0.11.2: undefined reference to `g2o::csparse_extension::writeCs2Octave(char const*, cs_sparse const*, bool)'
../../../bin/librtabmap_core.so.0.11.2: undefined reference to `g2o::csparse_extension::cs_chol_workspace(cs_sparse const*, cs_symbolic const*, int*, double*)'

The wrong csparse library is linked (between the one built from g2o and the one installed by the system). If the one in the system exists, the one built by g2o (because g2o was built before suitesparse was installed on the system) should be removed.

Solution: completly uninstall g2o and reinstall it. Clear the build directory of rtabmap and build again.

$ sudo rm -r /usr/local/include/EXTERNAL /usr/local/include/g2o
$ sudo rm -r /usr/local/lib/libg2o_*
$ cd g2o/build
$ rm -rf *
$ cmake ..
$ make -j4
$ sudo make install
$ cd rtabmap/build
$ rm -rf *
$ cmake ..
$ make -j4

[EasternH]

I think we can use cmake-gui to set the path of g2o. It usually in /usr/local/include