31 Jul
2016
31 Jul
'16
10:56 a.m.
Hi Andrew,
Andrew Burgess wrote,
* Andrew Burgess <andrew.burgess(a)embecosm.com>
[2016-07-29 10:43:17 +0100]:
Thanks, simplification is always good.
Applied and pushed,
Waldemar
* Alexey Brodkin
<Alexey.Brodkin(a)synopsys.com> [2016-07-29 08:49:22 +0000]:
Having looked at this a little more I think that we should merge the
section Alexey mentioned above. In the second instance (the one I
modified) we use the symbol _dl_start, while in the first we use
_DYNAMIC.
However, the comment in the first block makes it clear the symbol used
should be a global symbol, not a local, and _dl_start is a local
symbol.
The consequence of using a local here is that we end up with a
R_ARC_NONE relocation being generated again the .got.
[ The generation of the R_ARC_NONE is probably a bug, or at least a
lack of optimisation, but it is what happens with the current
upstream tools. ]
As the arc dynamic loader does not currently support patching
R_ARC_NONE during the bootstrap phase, if uClibc(-ng) is configured
without native threads, then currently we get a dynamic loader that
does not work.
So, I think we should collapse both sections, and make use of the
_DYNAMIC symbol instead of _dl_start. I've included a revised version
of patch 1/2 that includes this latest change. Hi Andrew, all,
On Thu, 2016-07-28 at 15:40 -0700, Vineet Gupta wrote:
I left the second block in as the two blocks use different symbols,
the native threads block uses _DYNAMIC, while the non-native uses
_dl_start.
I wasn't sure if this was significant, so left the the split in
place. If more knowledgeable folk believe these can be combined then
that's fine with me (so long as we combine on @pcl). On 07/28/2016 03:04 PM, Bernhard Reutner-Fischer
wrote:
>
> >
> > Indeed your 2/2 seems to be the most "past-proof" code change. So I
> > >
> > > would think it
> > > is indeed better and is something I should have done in the first
> > > place.
> > >
> > > @Alexey, @Vlad what say you ?
> uClibc traditionally supports the current stable release of binutils, which would
make it patch #1 I think.
>
But 2/2 works for both and makes actual binutils version moot. FWIW, ARC tools
don't as of last release didn't use the upstream/stable binutils, but we are
pretty close to that now though.
Personally I'd prefer to not add more conditional defines in uClibc but
make it a little-bit simpler.
I.e. either Vlad's patch or #1 from this series IMHO looks better.
It's been quite some time since we updated our tools with PCL support
and I'm not really sure if there's anybody interested in using ages old
tools with today's uClibc. We don't test such combinations and there could
be issues already in such combos.
BTW I noticed that Vlad's patch removes/reverts that thing as well:
http://cgit.uclibc-ng.org/cgi/cgit/uclibc-ng.git/commit/ldso/ldso/arc/dl-sy…
c5187
While Andrew just replaces ".&" construction with "@pcl".
I'm wondering which is the correct approach here?