/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/ is in libphobos-5-dev 5.5.0-12ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/dlfcn.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/elf.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/execinfo.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/libelf.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/link.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/sys/
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/sys/elf.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/sys/elf_386.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/sys/elf_SPARC.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/sys/elf_amd64.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/sys/elf_notes.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/sys/elftypes.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/sys/link.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/sys/priocntl.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/sys/procset.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/core/sys/solaris/sys/types.d