[lldb-dev] gdb-remote incompatibility with gdbserver?

[Pedro Alves via lldb-dev]

On 12/05/2017 11:17 PM, David Manouchehri wrote:
> Is there a user accessible setting to force on XML target descriptions
> in new-gdbsever?

In gdbserver?  Nope.

There's a setting in GDB to force it to not fetch descriptions,
which I found out today didn't actually work.  Fixed now in master [1].
GDB works fine against gdbserver with XML force-disabled, so

I suspect something else is going on.

Maybe a disagreement about who adjusts the PC after a breakpoint trap
between lldb and gdbserver?  (given the spurious SIGTRAPs and SIGSEGVs)
gdb and gdbserver negotiate that via  qSupported.  If both agree on
the "swbreak+" feature, then gdbserver handles it (and reports a "T05 swbreak"
for int3 traps).  Otherwise gdbserver assumes that the client (gdb/lldb) will,
so doesn't do it itself.  I did a quick grep on a lldb checkout I had
around here and didn't find any "swbreak" hit, but maybe lldb assumes
the server does it?

Really just guessing though.

[1] https://sourceware.org/ml/gdb-patches/2017-12/msg00121.html

Thanks,
Pedro Alves