Another fix attempt that appears to work

I have no idea why this works. Everything should already be single threaded
since it is run through the mainfunc channel. However, maybe there is some
implementation detail on the Windows platform that allocates the same
memory in a function call, and this is causing corruption. For some reason
locking the entire runQuery function works. Note, though, that putting the
locks *inside* the function itself doesn't work, but I'm not sure why.