[PATCH v4 02/11] gdb, remote: fix assertion on reconnect to non-stop target

From: "Bouhaouel, Mohamed" <[email protected]>

When reconnecting to a non-stop remote target, threads may retain stale
internal state from the previous connection (e.g., THREAD_INT_RUNNING).
This causes an assertion failure in
thread_info::set_pending_waitstatus(), which requires the thread to be
in THREAD_INT_STOPPED or THREAD_INT_RESUMED_PENDING_STATUS state.

Fix by setting thread's states before calling set_pending_waitstatus ()
in process_initial_stop_replies ().

Scenario:
    - Connect to non-stop remote target with running threads.
    - Disconnect (threads remain in THREAD_INT_RUNNING state).
    - Reconnect to same target.
    - process_initial_stop_replies() processes stop events.
    - Assertion fails when trying to set pending waitstatus on thread still
      marked as THREAD_INT_RUNNING.

Reproducible when running gdb.server/reconnect-ctrl-c.exp, on
native-gdbserver or native-extended-gdbserver with target-non-stop
enabled.

export GDBFLAGS="-iex \"maint set target-non-stop on\""
make check TESTS="gdb.server/reconnect-ctrl-c.exp" \
    RUNTESTFLAGS="--target_board=native-gdbserver GDBFLAGS='$GDBFLAGS'"
---
 gdb/remote.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/gdb/remote.c b/gdb/remote.c
index 194c4cbd9bb..7022e58abab 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -5177,12 +5177,13 @@ remote_target::process_initial_stop_replies (int from_tty)
 	  ws.set_stopped (sig);
 	}
 
+      set_internal_state (this, event_ptid, THREAD_INT_STOPPED);
+      set_state (this, event_ptid, THREAD_STOPPED);
+
       if (ws.kind () != TARGET_WAITKIND_STOPPED
 	  || ws.sig () != GDB_SIGNAL_0)
 	evthread->set_pending_waitstatus (ws);
 
-      set_internal_state (this, event_ptid, THREAD_INT_STOPPED);
-      set_state (this, event_ptid, THREAD_STOPPED);
       get_remote_thread_info (evthread)->set_not_resumed ();
     }
 
-- 
2.43.0

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