/usr/include/libGkArrays-2.1.0/ is in libgkarrays-dev 2.1.0+dfsg-1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/libGkArrays-2.1.0/binvect.hxx
/usr/include/libGkArrays-2.1.0/bitvector.cxx
/usr/include/libGkArrays-2.1.0/bitvector.hxx
/usr/include/libGkArrays-2.1.0/gkArrays.h
/usr/include/libGkArrays-2.1.0/gkArraysBuilder.h
/usr/include/libGkArrays-2.1.0/gkArraysTypes.h
/usr/include/libGkArrays-2.1.0/gkCFPSBuilder.h
/usr/include/libGkArrays-2.1.0/gkIFABuilder.h
/usr/include/libGkArrays-2.1.0/gkSABuilder.h
/usr/include/libGkArrays-2.1.0/kseq/
/usr/include/libGkArrays-2.1.0/kseq/kseq.h
/usr/include/libGkArrays-2.1.0/largebinvect.cxx
/usr/include/libGkArrays-2.1.0/largebinvect.hxx
/usr/include/libGkArrays-2.1.0/readsReader.h
/usr/include/libGkArrays-2.1.0/solArray.h
/usr/include/libGkArrays-2.1.0/sux/
/usr/include/libGkArrays-2.1.0/sux/macros.h
/usr/include/libGkArrays-2.1.0/sux/popcount.h
/usr/include/libGkArrays-2.1.0/sux/rank9b.h