/usr/share/openmpi/mpicxx-wrapper-data.txt is in openmpi-common 1.4.3-2.1ubuntu3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/openmpi/mpic++-wrapper-data.txt
/usr/share/openmpi/mpic++-wrapper-data.txt