From: "H.J. Lu" <hjl.tools@gmail.com>
To: Jeff Law <law@redhat.com>
Cc: Cary Coutant <ccoutant@gmail.com>, Michael Matz <matz@suse.de>,
"Maciej W. Rozycki" <macro@imgtec.com>,
Alan Modra <amodra@gmail.com>,
Richard Biener <richard.guenther@gmail.com>,
Joe Groff <jgroff@apple.com>, Binutils <binutils@sourceware.org>,
GCC <gcc@gcc.gnu.org>
Subject: Re: Preventing preemption of 'protected' symbols in GNU ld 2.26 [aka should we revert the fix for 65248]
Date: Mon, 25 Apr 2016 17:31:00 -0000 [thread overview]
Message-ID: <CAMe9rOr4Sic7AyzqZBbTWVYQQduL85FnkWK38mXf-PbZqTGX5Q@mail.gmail.com> (raw)
In-Reply-To: <18662de1-62db-2b44-ef50-2c04204e2521@redhat.com>
On Mon, Apr 25, 2016 at 10:24 AM, Jeff Law <law@redhat.com> wrote:
> On 04/18/2016 11:55 AM, Cary Coutant wrote:
>>>>
>>>> That is why protected visibility is such a mess.
>>>
>>>
>>> Not mess, but it comes with certain limitations. And that's okay. It's
>>> intended as an optimization, and it should do that optimization if
>>> requested, and error out if it can't be done for whatever reason.
>>
>>
>> I completely agree.
>
> ISTM this ought to be the guiding principle here, with the additional caveat
> that if one of the limitations is tickled that we issue a good diagnostic.
>
> The current situation (gcc-5, gcc-6-rc) essentially de-optimizes protected
> systems in an attempt to work around the various limitations of protected
> symbols. Reverting that change is, IMHO, what needs to happen. My worry is
> that we're so damn late in the gcc-6 cycle that it may need to be deferred
> to 6.2 or beyond.
Please keep in mind that many limitations can only be detected at
link-time or run-time, which are yet to be implemented, not at
compile-time.
--
H.J.
next prev parent reply other threads:[~2016-04-25 17:31 UTC|newest]
Thread overview: 57+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <AB592ABD-D6D7-4D2F-A0D6-45738F168DC4@apple.com>
2016-03-29 19:31 ` Fwd: Preventing preemption of 'protected' symbols in GNU ld 2.26 Joe Groff
2016-03-29 19:33 ` H.J. Lu
2016-03-29 19:36 ` Joe Groff
2016-03-29 19:43 ` H.J. Lu
2016-03-29 19:51 ` Joe Groff
2016-03-29 19:54 ` H.J. Lu
2016-03-29 22:05 ` H.J. Lu
2016-03-30 1:44 ` Alan Modra
2016-03-30 1:46 ` Cary Coutant
2016-03-30 4:04 ` Jeff Law
2016-03-30 7:20 ` Cary Coutant
2016-03-30 7:34 ` Cary Coutant
2016-03-30 14:44 ` Alan Modra
2016-03-31 0:45 ` Cary Coutant
2016-04-15 21:49 ` Preventing preemption of 'protected' symbols in GNU ld 2.26 [aka should we revert the fix for 65248] Jeff Law
2016-04-15 21:56 ` H.J. Lu
2016-04-18 9:02 ` Richard Biener
2016-04-18 14:49 ` Alan Modra
2016-04-18 14:59 ` H.J. Lu
2016-04-18 17:04 ` Maciej W. Rozycki
2016-04-18 17:09 ` H.J. Lu
2016-04-18 17:24 ` Michael Matz
2016-04-18 17:27 ` H.J. Lu
2016-04-18 18:52 ` Jakub Jelinek
2016-04-18 19:28 ` H.J. Lu
2016-04-18 17:55 ` Cary Coutant
2016-04-25 17:24 ` Jeff Law
2016-04-25 17:31 ` H.J. Lu [this message]
2016-04-18 17:57 ` Maciej W. Rozycki
2016-04-19 5:08 ` Alan Modra
2016-04-19 8:20 ` Richard Biener
2016-04-19 9:53 ` Szabolcs Nagy
2016-04-19 14:06 ` Michael Matz
2016-04-19 15:37 ` Cary Coutant
2016-04-19 15:44 ` H.J. Lu
2016-04-19 15:52 ` H.J. Lu
2016-04-19 15:54 ` H.J. Lu
2016-04-19 15:58 ` Cary Coutant
2016-04-19 16:00 ` H.J. Lu
2016-04-19 15:54 ` Cary Coutant
2016-04-19 19:11 ` H.J. Lu
2016-04-19 20:17 ` Rich Felker
2016-04-19 21:03 ` Cary Coutant
2016-04-20 17:45 ` anonymous
2016-04-19 15:46 ` Alan Modra
2016-04-25 17:35 ` Jeff Law
2016-04-26 5:55 ` Alan Modra
2016-04-26 8:13 ` Jakub Jelinek
2016-04-18 17:05 ` Cary Coutant
2016-03-31 0:40 ` Preventing preemption of 'protected' symbols in GNU ld 2.26 Cary Coutant
2016-03-31 0:53 ` Jeff Law
2016-03-31 13:27 ` Ramana Radhakrishnan
2016-03-31 15:05 ` H.J. Lu
2016-04-15 16:10 ` Szabolcs Nagy
2016-04-01 19:51 ` Jeff Law
2016-04-02 2:53 ` Alan Modra
2016-04-19 19:47 ` Fwd: " Rich Felker
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