[oi-dev] gdb 8.0 sol_thread_fetch_registers: td_ta_map_id2thr: no thread can be found to satisfy query

[Gordon Ross]

Anyone have any suggestions on how to track down this problem?

$ gdb fksmbd 5463
[...]
Attaching to program `.../usr/src/cmd/smbsrv/fksmbd/fksmbd', process 5463
Reading symbols...
[Thread debugging using libthread_db enabled]
[New LWP ... ] (50x)
[New Thread ...] (50x)
[Switching to Thread 1 (LWP 1)]
0xfe9970b5 in __sigtimedwait ()
   from .../proto/root_i386/lib/libc.so.1
(gdb) break debug_enter
Breakpoint 1 at 0xfee772b7: file ../common/printf.c, line 192.
(gdb) cont
Continuing.
fksmbd.debug: smbd_localtime_monitor: online
smbd_localtime_monitor: online
[New LWP    54        ]
[New LWP    55        ]
[LWP    54         exited]
[New LWP    56        ]
[New LWP    57        ]
[New Thread 57 (LWP 57)]
[LWP    56         exited]
[LWP    57         exited]
[New LWP    57        ]
[New Thread 55        ]
[Switching to Thread 57 (defunct)]
sol_thread_fetch_registers: td_ta_map_id2thr: no thread can be found
to satisfy query

This is happening often enough to make gdb unusable for me.
Failing with a defunct thread leads me to guess it's having trouble
getting the target process stopped before it starts looking around at
threads etc.
Suggestions appreciated.
Thanks!