/usr/ is in libclfft-dev 2.12.2-1build2.
This file is owned by root:root, with mode 0o755.
..
/usr/include/
/usr/include/clAmdFft.h
/usr/include/clAmdFft.version.h
/usr/include/clFFT.h
/usr/include/clFFT.version.h
/usr/lib/
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/cmake/
/usr/lib/x86_64-linux-gnu/cmake/clFFT/
/usr/lib/x86_64-linux-gnu/cmake/clFFT/clFFTConfig.cmake
/usr/lib/x86_64-linux-gnu/cmake/clFFT/clFFTConfigVersion.cmake
/usr/lib/x86_64-linux-gnu/cmake/clFFT/clFFTTargets-none.cmake
/usr/lib/x86_64-linux-gnu/cmake/clFFT/clFFTTargets.cmake
/usr/lib/x86_64-linux-gnu/pkgconfig/
/usr/lib/x86_64-linux-gnu/pkgconfig/clFFT.pc
/usr/share/
/usr/share/doc/
/usr/share/doc/libclfft-dev/
/usr/share/doc/libclfft-dev/copyright
/usr/lib/x86_64-linux-gnu/libclFFT.so
/usr/share/doc/libclfft-dev/changelog.Debian.gz