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Re: Switch on compiler hardening defaults

On Wed, 06 Jan 2010 09:29:42 +0100, Paul Wise wrote:
> > Hmm, OK. I'm quite surprised Fedora carries so many[1] patches to GDB,
> > 1. http://cvs.fedoraproject.org/viewvc/rpms/gdb/devel/

Temporarily current "devel" is:

(but you are right 99% of time it is normally /devel/)

> > given their policy of staying close to upstreams[2].
> >
> > Jan, as the maintainer of GDB in Fedora, can you comment on if/when
> > Fedora's many many GDB patches

GDB in recent years had no working upstream community.  After I spent a lot of
time preparing patches for upstream they usually got zero attention upstream.
	http://sourceware.org/ml/gdb-patches/2007-11/msg00438.html #0..6
Therefore I rather spent the time fixing problems of Red Hat customers.

Situation changed in a last year+ primarily thanks to Tom Tromey working for
Red Hat creating a new working upstream review & approving GDB community.
It is still not perfect but it is far better than before.

Still the Fedora patchset is large and it will take some time to merge it.
I am going to give it some more time this year as the duties permit.
Particularly thanks to the new PIE patch which finally made the Fedora
patchset more coherent and with more stable results in my eyes.

Generally downstream patches just make sense, such as:

The fix is fully working and it is a oneliner done in 5 minutes.  But the
right fix is to discuss a DWARF extension first at
<dwarf-discuss@lists.dwarfstd.org>, implement the concluded DWARF extension
producer in GCC and then implement the extension consumer in GDB.  I would not
manage to reach the current RHEL deadline such way.  And why not to put the
fully working fix also to Fedora when it has to be present in RHEL anyway.

Particularly the Archer project was IMHO created for more flexible development
model exchanging fast feature delivery for the cost of lower codebase
cleanliness; similar to the Fedora downstream patchset goals.

> > (particularly PIE support) will be merged upstream?

The former Red Hat PIE support by Jeff Johnston of Red Hat worked when it was
needed but it was not mergeable upstream as it was based on unfortunate
principles (it was checking addresses at the time of initialized ld.so shared
library list which is too late creating a chicken-and-egg problem).

> > Has there been any attempt thus far at getting them merged?

Therefore I rewrote it recently and posted the PIE patchset once:
	http://sourceware.org/ml/gdb-patches/2009-11/msg00167.html #0..15

But there were some updates since that time and I have not done a new merge
and repost so far:

This should hopefully happen now during January.

All the GDB patches/data I have available are public.  All the expressed
opinions are my personal ones unrelated to Red Hat or even the Archer


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