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Re: Preventing preemption of 'protected' symbols in GNU ld 2.26
- From: Jeff Law <law at redhat dot com>
- To: Cary Coutant <ccoutant at gmail dot com>
- Cc: "H.J. Lu" <hjl dot tools at gmail dot com>, Joe Groff <jgroff at apple dot com>, Alan Modra <amodra at gmail dot com>, Binutils <binutils at sourceware dot org>
- Date: Fri, 1 Apr 2016 13:51:33 -0600
- Subject: Re: Preventing preemption of 'protected' symbols in GNU ld 2.26
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On 03/30/2016 06:40 PM, Cary Coutant wrote:
It would help me immensely on the GCC side if things if you and Alan could
easily summarize correct behavior and the impact if we were to just revert
HJ's change. A testcase would be amazingly helpful too.
It looks like it's not just the one change. There's this patch:
https://gcc.gnu.org/ml/gcc-patches/2015-07/msg01871.html
which took the idea that protected can still be pre-empted by a COPY
relocation and extended it to three more targets that use COPY
relocations.
I wonder how many other patches have been based on the same misunderstanding?
The patches around BZ65780 may be tangled in this mess as well. And
it bled into the s390 & darwin ports as well.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65780
Alan, could you take a peek at 65780 -- you're better versed than I in
this stuff. Essentially the question that needs to be answered is if we
roll back 65280, do we need to also roll back 65780?
jeff