Can you please have a look if virtual/awk is sufficient or if gawk is needed.
bin/*.awk is posix-conform (no gensub(), or match() with 3rd argument), so virtual/awk should be fine.
+ 10 Mar 2013; Christoph Junghans <ottxor@gentoo.org> tiers-1.1.ebuild: + switch to virtual/awk (bug #455678)