Hi!

I just noticed that we're close to being able to eliminate
the old deprecated_add_set_cmd interface.  The only two commands
left using it are:

"maint show-debug-regs"

(gdb) help maint show-debug-regs
Set whether to show variables that mirror the x86 debug registers.
Use "on" to enable, "off" to disable.
If enabled, the debug registers values are shown when GDB inserts
or removes a hardware breakpoint or watchpoint, and when the inferior
triggers a breakpoint or watchpoint.

And, "maint gnu-debug"

(gdb) help maint gnu-debug
Set debugging output for the gnu backend.

The attached patch converts them to use the add_setshow
alternatives, in the least intrusive way.  Well, it has one
immediate benefit:  'maint show-debug-regs <tab>' now autocompletes:

(gdb) maint show-debug-regs o
off  on

However, the new interfaces (add_setshow_*) were added mainly because
every set command should be paired with a show command -- both these
commands in their current state have no way to let the user know the
status of the setting --- they're write-only.  While I'm at it, this
would be a good time to fix it up for these remaining commands.

Hence, the million dollar question:

Would you prefer the commands to stay as they are, or, to rename
the commands to be able to add a "show" facility ?

E.g., say, for the x86 debug registers debug output,

 maint show-debug-regs -> maint set show-debug-regs on|off
                          maint show show-debug-regs

Alternatively:

 maint show-debug-regs -> set debug debug-regs on|off
                          maint show debug-regs

?

And, for the gnu/hurd people debugging the debugger:

 maint gnu-debug -> maint set gnu-debug
                    maint show gnu-debug

Alternatively:

 maint gnu-debug -> set debug gnu (, gnu-nat, gnu-hurd, gnu-whatever, ...)
                    show debug gnu

?

-- 
Pedro Alves