cc  -O2 -Werror -Wall -Wextra -Wfloat-equal -Wformat=2 -Winit-self -Wmissing-format-attribute -Wmissing-noreturn -Wmissing-prototypes -Wnull-dereference -Wpointer-arith -Wshadow -Wstrict-prototypes -Wundef -Wunused -Wwrite-strings -fno-common -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -I../include -D_GNU_SOURCE -DNO_ANDROID_BACKEND -DUSE_PCRE2 -DPCRE2_CODE_UNIT_WIDTH=8 -DHAVE_STRLCPY -DHAVE_REALLOCARRAY  -shared -o libselinux.so.1 avc.lo avc_internal.lo avc_sidtab.lo booleans.lo callbacks.lo canonicalize_context.lo checkAccess.lo check_context.lo checkreqprot.lo compute_av.lo compute_create.lo compute_member.lo compute_relabel.lo compute_user.lo context.lo deny_unknown.lo disable.lo enabled.lo fgetfilecon.lo freecon.lo freeconary.lo fsetfilecon.lo get_context_list.lo get_default_type.lo get_initial_context.lo getenforce.lo getfilecon.lo getpeercon.lo init.lo is_customizable_type.lo label.lo label_db.lo label_file.lo label_media.lo label_support.lo label_x.lo lgetfilecon.lo load_policy.lo lsetfilecon.lo mapping.lo matchmediacon.lo matchpathcon.lo policyvers.lo procattr.lo query_user_context.lo regex.lo reject_unknown.lo selinux_check_securetty_context.lo selinux_config.lo selinux_internal.lo selinux_restorecon.lo sestatus.lo setenforce.lo setexecfilecon.lo setfilecon.lo setrans_client.lo seusers.lo sha1.lo stringrep.lo validatetrans.lo -lpcre2-8  -ldl -Wl,-soname,libselinux.so.1,--version-script=libselinux.map,-z,defs,-z,relro
ld.lld: error: undefined symbol: fts_open
>>> referenced by selinux_restorecon.c
>>>               selinux_restorecon.lo:(selinux_restorecon_common)
>>> referenced by selinux_restorecon.c
>>>               selinux_restorecon.lo:(selinux_restorecon_xattr)

ld.lld: error: undefined symbol: fts_read
>>> referenced by selinux_restorecon.c
>>>               selinux_restorecon.lo:(selinux_restorecon_common)
>>> referenced by selinux_restorecon.c
>>>               selinux_restorecon.lo:(selinux_restorecon_xattr)
>>> referenced by selinux_restorecon.c
>>>               selinux_restorecon.lo:(selinux_restorecon_xattr)
>>> referenced 1 more times

ld.lld: error: undefined symbol: fts_close
>>> referenced by selinux_restorecon.c
>>>               selinux_restorecon.lo:(selinux_restorecon_common)
>>> referenced by selinux_restorecon.c
>>>               selinux_restorecon.lo:(selinux_restorecon_xattr)
>>> referenced by selinux_restorecon.c
>>>               selinux_restorecon.lo:(selinux_restorecon_xattr)

ld.lld: error: undefined symbol: fts_set
>>> referenced by selinux_restorecon.c
>>>               selinux_restorecon.lo:(selinux_restorecon_xattr)
>>> referenced by selinux_restorecon.c
>>>               selinux_restorecon.lo:(selinux_restorecon_thread)
cc: error: linker command failed with exit code 1 (use -v to see invocation)