Fixing the glibc adobe flash incompatibility

Matthew Garrett mjg59 at
Thu Nov 18 04:32:55 UTC 2010

On Wed, Nov 17, 2010 at 10:30:00PM -0600, Chris Adams wrote:
> Once upon a time, Matthew Garrett <mjg59 at> said:
> > On Wed, Nov 17, 2010 at 09:03:02PM -0600, Chris Adams wrote:
> > > However, I still think that changing memcpy away from years of "it just
> > > works" is an ABI change that should not be taken lightly and IMHO
> > > shouldn't be done in a "stable" release of glibc.  Is memcpy called
> > > often enough (and on large enough blocks) that this change makes a real
> > > performance difference (not just on a synthetic memcpy benchmark)?
> > 
> > It's a change in behaviour on x86. Have you verified that overlapping 
> > memcpy worked on all other glibc-supported architectures until this 
> > point?
> How is that relevant?  If the behavior changes on only some
> architectures, then it is okay?

If it's broken on non-x86 already then there haven't been "years of 'it 
just works'".

Matthew Garrett | mjg59 at

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