4.0 regression: missing debug info for global variables in C with -O2

[Paolo Bonzini]

> > Yes; in fact 'main' is even superfluous.  Just compile
> >
> >  int var;
> >
> > with -S -O2 -g on gcc 3.4 and 4.0 and look at the resulting
> > assembler file, the difference is quite obvious ...

Maybe this is responsible for part of PR21828?

Paolo