Thanks for thinking of offering your changes back to the community of GDB users. In general we like to get well designed enhancements. Thanks also for checking in advance about the best way to transfer the changes.
The two main problems with getting your patches in are,
I don't know how to get past these problems except by continuing to try.
There are two issues here -- technical and legal.
The legal issue is that to incorporate substantial changes requires a
copyright assignment from you and/or your employer, granting ownership
of the changes to the Free Software Foundation. You can get the
standard document for doing this by sending mail to
gnu@prep.ai.mit.edu and asking for it. I recommend that people
write in "All programs owned by the Free Software Foundation" as "NAME
OF PROGRAM", so that changes in many programs (not just GDB, but GAS,
Emacs, GCC, etc) can be contributed with only one piece of legalese
pushed through the bureacracy and filed with the FSF. I can't start
merging changes until this paperwork is received by the FSF (their
rules, which I follow since I maintain it for them).
Technically, the easiest way to receive changes is to receive each feature as a small context diff or unidiff, suitable for "patch". Each message sent to me should include the changes to C code and header files for a single feature, plus ChangeLog entries for each directory where files were modified, and diffs for any changes needed to the manuals (gdb/doc/gdb.texi or gdb/doc/gdbint.texi). If there are a lot of changes for a single feature, they can be split down into multiple messages.
In this way, if I read and like the feature, I can add it to the sources with a single patch command, do some testing, and check it in. If you leave out the ChangeLog, I have to write one. If you leave out the doc, I have to puzzle out what needs documenting. Etc.
The reason to send each change in a separate message is that I will not install some of the changes. They'll be returned to you with questions or comments. If I'm doing my job, my message back to you will say what you have to fix in order to make the change acceptable. The reason to have separate messages for separate features is so that other changes (which I am willing to accept) can be installed while one or more changes are being reworked. If multiple features are sent in a single message, I tend to not put in the effort to sort out the acceptable changes from the unacceptable, so none of the features get installed until all are acceptable.
If this sounds painful or authoritarian, well, it is. But I get a lot of bug reports and a lot of patches, and most of them don't get installed because I don't have the time to finish the job that the bug reporter or the contributor could have done. Patches that arrive complete, working, and well designed, tend to get installed on the day they arrive. The others go into a queue and get installed if and when I scan back over the queue -- which can literally take months sometimes. It's in both our interests to make patch installation easy -- you get your changes installed, and I make some forward progress on GDB in a normal 12-hour day (instead of them having to wait until I have a 14-hour or 16-hour day to spend cleaning up patches before I can install them).
Please send patches to bug-gdb@prep.ai.mit.edu, if they are less
than about 25,000 characters. If longer than that, either make them
available somehow (e.g. anonymous FTP), and announce it on
bug-gdb, or send them directly to the GDB maintainers at
gdb-patches@cygnus.com.