Re: Hunting for performance regressions in libstdc++

[Jonathan Wakely <cow at compsoc dot man dot ac dot uk>]

On Thu, Jun 16, 2005 at 12:53:45PM +0100, Jonathan Wakely wrote:

> On Wed, Jun 15, 2005 at 09:09:54PM -0700, Dan Kegel wrote:
> 
> > I have a sneaking suspicion that some of my app's
> > performance problems might be due to gcc-3.4.3's libstdc++
> > being somehow slower than SGI's STL, so I'm planning
> > on doing some performance testing of various implementations
> > of STL.
> 
> You aren't, by any chance, using std::set::insert() with hints ?
> 
> We changed the behaviour of that function recently to conform to the
> standard, which contradicts the traditional meaning of the hint. If
> you are supplying a hint that points just before the insertion point
> you will not get any speed-up.

Paolo kindly pointed out to me that the mail I quoted includes
"gcc-3.4.3's libstdc++" which means that a change we made in 4.0.0
can't be related!

Can I plead stupidity as a defence?  ;)

jon

-- 
"You're not drunk if you can lie on the floor without holding on."
	- Dean Martin