devel/help2man uses a .tar.xz distfile, if archivers/xz is not installed, you can't build it because xzdec is not installed.
Index: Makefile =================================================================== RCS file: /cvs/ports/devel/help2man/Makefile,v retrieving revision 1.24 diff -u -p -r1.24 Makefile --- Makefile 2 Apr 2018 08:42:31 -0000 1.24 +++ Makefile 26 Jul 2018 09:13:58 -0000 @@ -12,6 +12,8 @@ HOMEPAGE= https://www.gnu.org/software/h # GPLv3 PERMIT_PACKAGE_CDROM= Yes +BUILD_DEPENDS= archivers/xz + SEPARATE_BUILD= Yes NO_TEST= Yes
