DATA_MASTER_SITES= https://9fans.github.io/plan9port/dist/ 404 not found.
Sorry, I misunderstood the Makefile, overlooked the DATA_DISTFILES= line. These _do_ exist: <https://9fans.github.io/plan9port/dist/pgw.tar.bz2> <https://9fans.github.io/plan9port/dist/roget.tar.bz2> <https://9fans.github.io/plan9port/dist/scat.tgz>