/usr/libx32/debug/libstdc++.so is in libx32stdc++6-4.7-dbg 4.7.3-12ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/libx32/debug/libstdc++.so.6.0.17
/usr/libx32/debug/libstdc++.so.6.0.17