$(if $(dl_pack/$(call ext,$(1))),$(dl_pack/$(call ext,$(1))),$(dl_pack/unknown))
endef
define dl_tar_pack
- $(TAR) --owner=0 --group=0 --sort=name $$$${TAR_TIMESTAMP:+--mtime="$$$$TAR_TIMESTAMP"} -c $(2) | $(call dl_pack,$(1))
+ $(TAR) --numeric-owner --owner=0 --group=0 --sort=name $$$${TAR_TIMESTAMP:+--mtime="$$$$TAR_TIMESTAMP"} -c $(2) | $(call dl_pack,$(1))
endef
define DownloadMethod/unknown