Gnat toolbox
Those programs are part of GNU GNAT, a freely available Ada 95 compiler.
For accessing the full GNAT manuals, use info gnat-ug-4.8 and info gnat-rm-4.8 for the sections related to the reference manual. If those sections cannot be found, you will have to install the gnat-4.4-doc package as well (since these manuals contain invariant parts, the package is located in the non-free part of the Debian archive). You may also browse http://gcc.gnu.org/onlinedocs which provides the GCC online documentation.
This manpage has been written by Samuel Tardieu <[email protected]>, for the Debian GNU/Linux project.