[Patch] Fix istream::ignore + minor things

[Paolo Carlini]

Martin Sebor wrote:

> I chose IPF over IA32 because the processor's instruction set
> includes branch prediction hints

Interesting, I didn't know that, honestly.

> (plus, pretty much anybody has
> access to an IA32 box so if they're interested they can easily
> see the effect of the hint there :).

I hear you ;)

Thanks again: we should analyze carefully this data, check whether 
something has changed in gcc3.4/mainline in the branch prediction area 
(*), and definitely interact with the compiler people. I appreciate even 
more you help since goes exactly in the direction of a stricter 
collaboration with the compiler people in dealing with performance 
issues, something I mean to pay *much* more attention to in the future.

Paolo.

(*) At least, check what happens wrt the recent profile-directed 
optimizations!