Re: [PATCH] improve performance of std::allocator::deallocate

[Jonathan Wakely <jwakely at redhat dot com>]

On 20/05/19 09:17 +0000, Pádraig Brady wrote:
> On 04/02/2019 07:33 PM, Padraig Brady wrote:
> > On 03/07/2019 03:43 AM, Jonathan Wakely wrote:
> > > OK, that makes me feel better about it. It's presumably much easier to
> > > upgrade to 5.2 from 5.0 or 5.1 than it would be from 4.x.
> > >
> > > > > How complicated is the fix to prevent the crashes? Would it be
> > > > > feasible for distros to backport that fix? I see that RHEL8 has
> > > > > jemalloc 5.0.1 for example, but if the fix could be backported to that
> > > > > release then it's less of a problem.
> > > > The patch set is simple enough:
> > > > https://github.com/jemalloc/jemalloc/pull/1341/commits
> > > Thanks. That does seem reasonable for distros and other packagers to
> > > backport, if they want to support 5.0 or 5.1 for their users.
> > >
> > > I'm leaning towards accepting the patch for gcc-9 (and if not, we
> > > should do it early in the gcc-10 cycle).
> > FYI jemalloc 5.2 is released with the fix for zero sized deallocations:
> > https://github.com/jemalloc/jemalloc/releases/tag/5.2.0
> Friendly ping.
> I can create a bug to track if you prefer.

No thanks, patches belong on these lists.

Now that we're in GCC 10 development stage 1 I'm happy to apply the
patch. I think by the time GCC 10 is released it will be reasonable to
expect people to use the fixed version of jemalloc.

I'll do the change today.