Major - P3 Bug in unreleased code, I noticed this from a valgrind message while testing my transactions changes:
Begin /transactions/error-labels, seed 1002976610 (snip) - add unknown commit label to writeConcernError ShutdownInProgress ==26085== Conditional jump or move depends on uninitialised value(s) ==26085== at 0x596DFD: _mongoc_server_description_set_error (mongoc-server-description.c:470) ==26085== by 0x596F1F: mongoc_server_description_handle_ismaster (mongoc-server-description.c:519) ==26085== by 0x5A3E78: mongoc_topology_description_handle_ismaster (mongoc-topology-description.c:1940) ==26085== by 0x5A2D0A: mongoc_topology_description_invalidate_server (mongoc-topology-description.c:1128) ==26085== by 0x5A0A41: mongoc_topology_invalidate_server (mongoc-topology.c:924) ==26085== by 0x568E5E: handle_not_master_error (mongoc-cluster.c:460) ==26085== by 0x5691C2: mongoc_cluster_run_command_monitored (mongoc-cluster.c:575) ==26085== by 0x564ACA: _mongoc_client_command_with_stream (mongoc-client.c:1609) ==26085== by 0x56532A: _mongoc_client_command_with_opts (mongoc-client.c:1852) ==26085== by 0x56552A: mongoc_client_write_command_with_opts (mongoc-client.c:1913) ==26085== by 0x598C2B: txn_finish (mongoc-client-session.c:149) ==26085== by 0x59A101: mongoc_client_session_commit_transaction (mongoc-client-session.c:788) ==26085== by 0x46C4E3: commit_transaction (json-test-operations.c:1269)
In handle_not_master_error we call _check_not_master_or_recovering_error. If the server reply is something like this:
{
"ok": 1.0,
"writeConcernError": {
"code": 91,
"errmsg": "Replication is being shut down"
}
}
... then the passed-in bson_error_t is uninitialized, because there wasn't a normal server error, but handle_not_master_error nevertheless passes the error down to mongoc_topology_invalidate_server.