[poky] gdb readline problems (1.8 and 2.0.1)

[Jonah Petri]

Hello!
Does anyone know why some gdbs (in this case 7.8.1 and 7.9.1, as built
into a jethro or fido sdk) might not have working tab completion?

If I type "break wr" and then press <tab>, it does nothing.  However
gdb does know about the symbols!  To wit, if I type:
(gdb) complete b wr<return>
b write
b write at got.plt
b write at plt
b writer.h

So, the completions are there, but something is not hooked up
properly... Strangely, it seems that the tab key is hooked up to
something, as when I press <tab> from an empty gdb prompt, I get lots
of good completions, like "actions", "add-auto-load-safe-path", etc.
However, completion on symbols, like "write" above, seems to not work.

I have one possible solution for this, which is a bbappend file like so:
EXTRA_OECONF_append = " --without-system-readline"
...but I'm not sure why I would be the only one to notice this problem!

FWIW I'm building Jethro on top of Ubuntu 15.10.

Do others experience completion issues with GDB?  Or maybe everyone
else is using a GUI layer on top?  I never realized how much I depend
on tab completion for productivity while debugging, so any help would
be much appreciated!

Thanks!