How to see just mtree violations?

[Ryan Schmidt]

Not to say that I liked it better when mtree violations were fatal,  
but when they were, it was at least possible to easily notice the  
mtree violation. Now that it's only a warning in debug mode, it's too  
easily swallowed up by the deluge of other debug messages being  
printed before and after the mtree check. Before, we have configure,  
make and make install output, and after, we have activation output.  
In even medium-sized software packages, these can easily be hundreds  
of lines.

We have the -t switch which we can turn on separately to activate  
trace mode, which is helpful for discovering undeclared dependencies.  
Is there a way that we could somehow see just the mtree violations,  
without all the other verbose/debug info?