Re: Enable SSA at -O0

[Mark Mitchell <mark at codesourcery dot com>]

Richard Guenther wrote:

> > My biggest concern is that this may degrade debugging. We have
> > done quite a number on -O1 debuggability, and I am quite concerned
> > about this issue. if we can really be sure that there is zero or
> > positive impact on debugging and no other negatives, I have no
> > objection.
>
> How can we be "really sure"? 

We can't be.  That's the point. :-)

Since we have a lot of risk-inducing things that we've already 
prioritized for 4.4, and since time is short, I want to avoid adding 
another risk for this release.  When this goes into 4.5, we'll have 
plenty of time to correct any problems that arise.  Since this patch 
doesn't seem to provide any immediate benefit (but rather provides the 
infrastructure needed for other projects that would themselves add 
benefits, but with some associated risks), the timing just doesn't seem 
right.

Thanks,

--
Mark Mitchell
CodeSourcery
mark@codesourcery.com
(650) 331-3385 x713