GCC 3.0.3 PRs

[Joe Buck]

I wrote:
> > I think that 3720 should be considered a must-fix.  If people use stream
> > I/O in security-critical programs, this kind of buffer overflow could lead
> > to root exploits in programs that would be perfectly safe with a
> > correct iostreams implementation.  I don't think it's ethical for us to
> > ship with such a bug.

Mark writes:
> Well, OK.  Of course, any code-gen bug could lead to the same kinds
> of problems.  Still, I see your point.

This one is bad because it's pervasive: *any* attempt to read a number
can trigger a buffer overflow.  The only workaround is for people not
to use stream I/O to read numbers *at all*.  It's that bad.  Even

	int i;
	cin >> i;

can be made to crash, just type a whole lot of digits.  (I haven't
verified whether it's possible to force the program to execute arbitrary
code, but I wouldn't be surprised if it is).

> > Also, it shouldn't be hard to fix it once agreement is reached on how.
> > All that's needed is an upper bound on buffer size.
> 
> Benjamin, can you work on this ASAP?  Otherwise, I'll threatent to
> engineer my own quick fix for the branch to make Joe happy, but you'll
> probably not like how I do it. :-)

There's already a fix in the trunk, but it appears to be incorrect and slow.
Still, it's better than nothing.