/usr/include/osl/bits/ is in libosl-dev 0.8.0-1.4.
This file is owned by root:root, with mode 0o755.
..
/usr/include/osl/bits/additionalOrShadow.h
/usr/include/osl/bits/align16New.h
/usr/include/osl/bits/binaryIO.h
/usr/include/osl/bits/bitXmask.h
/usr/include/osl/bits/boardMask.h
/usr/include/osl/bits/boardTable.h
/usr/include/osl/bits/centering5x3.h
/usr/include/osl/bits/construct.h
/usr/include/osl/bits/directionTraits.h
/usr/include/osl/bits/effectContent.h
/usr/include/osl/bits/effectedNumTable.h
/usr/include/osl/bits/king8Info.h
/usr/include/osl/bits/mask.h
/usr/include/osl/bits/numBitmapEffect.h
/usr/include/osl/bits/numSimpleEffect.h
/usr/include/osl/bits/numSimpleEffect.tcc
/usr/include/osl/bits/offset32.h
/usr/include/osl/bits/pieceMask.h
/usr/include/osl/bits/pieceMask64.h
/usr/include/osl/bits/pieceStand.h
/usr/include/osl/bits/pieceTable.h
/usr/include/osl/bits/ptypeTable.h
/usr/include/osl/bits/ptypeTraits.h
/usr/include/osl/bits/quadInt.h
/usr/include/osl/bits/squareCompressor.h