gpr2make1
Gnat toolbox
Part of gnat(1).
Overview
Those programs are part of GNU GNAT 3.4, a freely available Ada 95 compiler.
For accessing the full GNAT manuals, use info gnat-ug-3.4 and info gnat-rm-3.4 for the sections related to the reference manual. If those sections cannot be found, you will have to install the gnat-3.4-doc package as well.