Here's a draft gtkada-2.4.0.ebuild. I have only tried it with gnat 3.4.1, which is in ~x86. Reproducible: Always Steps to Reproduce:
Created attachment 46865 [details] New gtkada-2.4.0.ebuild
Created attachment 46866 [details] Updated Manifest icluding the new ebuild.
The summary should read "2.4.0" rather than "2.40".
Thank you for the ebuild Bobby, I added it to portage a while ago but forgot to close the bug.