 re-run |install_mex|.
% 
% 2) Locate the system version of libstdc++.so.6 and create an alias in .bashrc 
% for MATLAB to use this one, for example: |alias matlab='LD_PRELOAD=/usr/lib/x86_64-linux-gnu/libstdc++.so.6 
% /path/to/MATLAB/bin/matlab -desktop'|. Or simply run MATLAB with the same |LD_PRELOAD|.
% 
% 3) Rename the libstdc++.so.6 file that ships with MATLAB, located in |/path/to/MATLAB/sys/os/glnxa64/|e.g. 
% |sudo mv /path/to/MATLAB/sys/os/glnxa64/libstdc++.so.6 /path/to/MATLAB/sys/os/glnxa64/lib