Fixing namespace issues for variables

[Roland McGrath]

It's some unpleasant contortion, but I can't think of anything else.
My main concern was about the issue of declaring without the header.
But if you can cite chapter and verse of the standards that says
it's OK (put this in code comments somewhere), then OK.  However,
I'm still worried about effectively taking these identifiers out of
the usable name space for other kinds of identifiers (member names,
locals, etc.).  Even if the standards permit it, it might break some
existing source code and it's certainly not a friendly thing to do
when we can avoid it.  But as I said, I haven't thought of anything
else to do instead.