Comment about an issue scan-build found.

It relates to a variable that is set, but never used.  I'm not sure if I
should use that variable (and remove a related one), or use the one I'm using
now.
Address some issues that scan-build found.

All releate to a stack-based variable stored in a global variable outlasting
the function it was defined in.

I'm still slowly working my way thorugh the global variable issue.