AC_CHECK_FUNCS([memfd_create])
AC_CHECK_FUNCS([__secure_getenv secure_getenv])
AC_CHECK_DECLS([gettid, pivot_root, name_to_handle_at, setns, LO_FLAGS_PARTSCAN],
AC_CHECK_FUNCS([memfd_create])
AC_CHECK_FUNCS([__secure_getenv secure_getenv])
AC_CHECK_DECLS([gettid, pivot_root, name_to_handle_at, setns, LO_FLAGS_PARTSCAN],