Status of gcc-gnat?

[list_email at icloud.com]

plplot comes with Ada bindings. Does MacPorts compile these Ada bindings? And...

...Does MacPorts support GNAT, the gcc Ada compiler? I see it listed as gcc-gnat, so that seems to imply “yes”. The reason I ask is that I remember some  years ago someone saying that GNAT is a problem because of MacPorts not using outside software, and that GNAT couldn’t be bootstrapped since it compiles itself.

What is the meaning of the gnat-gcc variants ada, gnatgpl, gnuada, and macada? Which should I use?

Jerry