[lldb-dev] Question about remote debugging protocol setup

[Matthew Gardiner]

Hi All,

I'm trying to understand how to write a gdbserver for one of our chips, 
which we are planning to attach lldb to.

First off, I started doing a sniff of protocol between debugger and 
gdbserver with local debug of an linux intel 64-bit process.

I then compared the traces between the debugger being gdb and lldb.

Using gdb:

CLIENT SENDS: +
CLIENT SENDS: $qSupported:multiprocess+;xmlRegisters=i386;qRelocInsn+#b5
SERVER SENDS: +
SERVER SENDS: 
$PacketSize=3fff;QPassSignals+;QProgramSignals+;qXfer:libraries-svr4:read+;augmented-libraries-svr4-read+;qXfer:auxv:read+;qXfer:spu:read+;qXfer:spu:write+;qXfer:siginfo:read+;qXfer:siginfo:write+;qXfer:features:read+;QStartNoAckMode+;qXfer:osdata:read+;multiprocess+;QNonStop+;QDisableRandomization+;qXfer:threads:read+;ConditionalTracepoints+;TraceStateVariables+;TracepointSource+;DisconnectedTracing+;FastTracepoints+;StaticTracepoints+;InstallInTrace+;qXfer:statictrace:read+;qXfer:traceframe-info:read+;EnableDisableTracepoints+;QTBuffer:size+;tracenz+;ConditionalBreakpoints+;BreakpointCommands+;QAgent+;Qbtrace:bts+;Qbtrace:off+;qXfer:btrace:read+#ad
SERVER SENDS: +
CLIENT SENDS: $QStartNoAckMode#b0
SERVER SENDS: +
SERVER SENDS: $OK#9a
CLIENT SENDS: +

Using lldb:

CLIENT SENDS: +
CLIENT SENDS: $QStartNoAckMode#b0
SERVER SENDS: +
CLIENT SENDS: $OK#9a
SERVER SENDS: +

So I'm wondering why does lldb not send the qSupported request? Is it a 
deliberate omission or is this still a work in progress?

All viewpoints appreciated,
thanks Matt




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