Mongodb C++ driver, failure at cleanup - c++

Question

I have a small program that tries to connect to mongodb and check how many objects it would receive if I could hope to receive objects. In the event, I can't even get a count of objects, and I segfault on cleanup even if I do nothing but connect.
I'm using the GlobalInstance object to maintain my connection and clean up for me at exit. This function I call from main. The program doesn't really do anything else yet.
Any suggestions on what I'm doing wrong that I segfault? Presumably this is related to not being able to call connection->count()?
Many thanks for any pointers.
int foo() {
mongo::client::Options options;
options.setSSLMode(mongo::client::Options::kSSLRequired);
mongo::client::GlobalInstance mongo_connection(options);
mongo::DBClientBase* connection;
if (!mongo_connection.status().isOK()) {
cout << "Mongo connection not established: "
<< mongo_connection.status() << endl;
}
try {
mongo::DBClientConnection c(true);
string error;
ostringstream mongo_url;
mongo_url << "mongodb://" << db_username << ":" << db_password << "#"
<< db_host << ":" << db_port << "/" << db_name;
const mongo::ConnectionString conn_string =
mongo::ConnectionString::parse(mongo_url.str(), error);
if (!conn_string.isValid()) {
cout << "Bad connection string: " << error << endl;
}
// Reality check. Passes.
cout << "user=" << conn_string.getUser() << endl;
cout << "pass=" << conn_string.getPassword() << endl;
cout << "db= " << conn_string.getDatabase() << endl;
const auto servers = conn_string.getServers();
for (const auto& server : servers) {
cout << "serv=" << server << endl;
}
cout << "type=" << conn_string.type() << endl;
// End reality check.
connection = conn_string.connect(error);
cout << "error says: " << error << endl; // Is empty.
cout << "conn=" << connection << endl; // Not zero.
std::cout << "connected ok" << std::endl;
cout << connection->getConnectionId() << endl; // Prints "1".
// This returns an error 13, not authorized, if I included it.
//cout << "count: " << connection->count("focus_groups") << endl;
} catch( const mongo::DBException &e ) {
std::cout << "caught " << e.what() << std::endl;
}
cout << "----------------------------------------------------------------------" << endl;
return 0;
}
/*
Note that I can do this in the mongo shell with no problem:
jeff#siegfried:~ $ mongo my_host:27017/my_db --ssl -u my_user -p
MongoDB shell version: 2.6.3
Enter password:
connecting to: my_host:27017/my_db
> db.focus_groups.count()
26
>
*/
I am running on 64 bit ubuntu 15.04 and compiling with clang 3.6.0. Boost is 1.55 installed via apt-get. The legacy mongo C++ driver I compiled and installed from git at HEAD (861699d116627d63e1c914384a66e4e3ea7c23bc) with ssl support.

Answer 1

This turned out to be a confluence of several things, but at least these two:
When I compiled the legacy driver, the default mode is C++03, which is not binary compatible with C++11 or C++14.
The driver is sensitive to differences in the version of boost with which it and the client using it are compiled.
An extensive thread appears here.