GCC 4.5 Status Report (2009-09-19)

[Richard Guenther]

On Sun, 20 Sep 2009, Dave Korn wrote:

> Richard Guenther wrote:
> 
> > The trunk is in Stage 1.  Stage 1 will end on Sep 30th.  After Stage 1
> > Stage 3 follows with only bugfixes and no new features allowed. 
> > Stage 3 will end Nov 30th.

I'll answer your and Jacks question together.

>   I don't think this is the best time to do that.  Trunk's been broken most of
> last week and will probably not be buildable for at least several days yet, so
> a big chunk of that warning period is going to be useless to many people.

The effective useless period is extended by not including the 2-3 days
necessary for the LTO merge in Stage 1.

> > We've been accumulating quite a number of P1 bugs.  Entering Stage 3
> > should allow to improve considerably here in a short time.
> 
>   So aren't we now likely to lose the first few days of what little remains of
> stage 1 waiting for trunk to start working again, then have a mad rush of
> people falling all over each other to get their new features in in the last
> couple of days?  One of which will inevitably break trunk again and block all
> the others and then stage 1 will be over and it'll all be too late?

I am not aware of any big patches that are still pending.  Coming up
with new yet unknown things now wouldn't be a good timing anyway.

>   Ten days isn't even that much warning in the first place; it's less time
> than you'd generally let elapse before pinging a patch.  Can I at least raise
> the suggestion that a plan that might work well would be for us to go slush
> for however long - less than a week, I'd suppose - it takes us to get trunk
> really properly stable, and then push back the end of stage 1 by that amount?

Note that Stage 3 isn't that strict as it may sound.  Maintainers have
quite amount of flexibility deciding what is considered a bug and thus
a bugfix during Stage 3 (note that Stage3 is _not_ only for regression
fixes).  This includes obviously Graphite and LTO as well as target
specific changes.

What you won't see in Stage 3 is rewrites of infrastructure or adding of
new optimization passes.

Note that we have been in Stage 1 for about six month now which is
IMHO enough (and unsurprisinlgy matches the length of Stage 1 of GCC 4.4).

Richard.