[cft] aligning main's stack frame

[Kean Johnston]

> This should get more than just bootstrap testing.  Anyone care to
> help out here?
I'm bringing my mainline tree up to speed, as all the porting work
I recently did was on the 4.0 branch, but once that's done I'll
be glad to help out. Aside from the full testsuite, I will compile
up Xorg and an internal package I have which is a collection of
about 70 different open source libraries (gtk, cairo, libxml2 etc)
and perl and apache/php. If that all works, then thats about as
well tested as I can think to get. Its a lot of code, some of
which really stresses the compiler (Xorg and Perl in particular).

Kean