/usr/share/man/man1/llvm-diff.1.gz is in llvm 1:3.4-0ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man1/llvm-diff-3.4.1.gz
/usr/share/man/man1/llvm-diff-3.4.1.gz