GCC warnings for unused global variables

[Bonzini]

> | I also forgot to mention the GCC policy of abandoning a release branch
> | soon after the .0 release.  Software vendors have to chase the GCC
> | releases to get bug fixed.
> 
> I cannot let this one pass: We got *four* dot releases from
> 3.1-branch;  the last three were named 3.2.1, 3.2.2, 3.2.3.   They all
> were bug fix releases.  Please don't spread misinformation. 

I think he was referring to abandoning the 3.2 branch after 3.3.0 is released.

Paolo