RFC: __FUNCTION__ and __PRETTY_FUNCTION__

[DJ Delorie]

> Andreas suggested deprecating it in 3.1 and removing it 3.2, which
> is definitely less dodgy -- but also means we have to remember this
> debate for several more months -- at least until after we branch for
> 3.1 in February.

Could we add a commented #if in a relevent part of the gcc sources
that triggers off the 3.2 version number and causes a compile error?
Then at least the person bumping the version number can remove the
error and post a note to restart the discussion.