In the current master version, this wont compile:

#include <assert.h>
#include "mongo/client/dbclient.h"
int main()
{
assert(0);
return 0;
}

I just get the following error:

test.cpp: In function 'int main()':
test.cpp:5: error: 'assert' was not declared in this scope

I looks like mongo redefines the assert macro, this is an unexpected, and undesired side effect.