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From: Florian Weimer <fweimer@redhat.com>
To: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
Cc: "H.J. Lu" <hjl.tools@gmail.com>,
	 Wilco Dijkstra via Libc-alpha <libc-alpha@sourceware.org>,
	 Szabolcs Nagy <Szabolcs.Nagy@arm.com>
Subject: Re: [PATCH 2/3] Revert "[AArch64][BZ #17711] Fix extern protected data handling"
Date: Thu, 26 May 2022 21:25:45 +0200	[thread overview]
Message-ID: <8735gwhz9i.fsf@oldenburg.str.redhat.com> (raw)
In-Reply-To: <AM5PR0801MB1875D0A358387E28C926E8D883D99@AM5PR0801MB1875.eurprd08.prod.outlook.com> (Wilco Dijkstra's message of "Thu, 26 May 2022 19:17:49 +0000")

* Wilco Dijkstra:

> Hi,
>
>>> What about -flto (with a linker plugin)?
>>
>>
>> LTO certainly works.  An undefined symbol will be imported from a shared
>> library.
>
> LTO allows you to determine which symbols are imported indeed, so the
> compiler can use a GOT indirection without requiring explicit import
> annotations.
>
> However LTO does not solve all the code quality issues of FPIC - there
> is still no inlining, internal calls indirect via the PLT and
> non-static globals use a GOT indirection.

Could you share a small example that exhibits these shortcomings?

Thanks,
Florian


  reply	other threads:[~2022-05-26 19:25 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-05-24 13:46 Wilco Dijkstra
2022-05-24 17:28 ` maskray
2022-05-24 21:58 ` H.J. Lu
2022-05-25 17:13   ` Wilco Dijkstra
2022-05-25 18:21     ` Florian Weimer
2022-05-25 20:44       ` H.J. Lu
2022-05-26 19:17         ` Wilco Dijkstra
2022-05-26 19:25           ` Florian Weimer [this message]
2022-05-26 20:03             ` Wilco Dijkstra
2022-05-26 21:27               ` H.J. Lu
2022-05-27 12:43               ` Florian Weimer
2022-05-31  2:03                 ` H.J. Lu
2022-05-31  7:49                   ` Fangrui Song
2022-05-31  9:42                     ` Wilco Dijkstra
2022-05-31 13:47                     ` H.J. Lu
2022-05-31  7:42               ` Fangrui Song
2022-05-25 20:10     ` maskray
  -- strict thread matches above, loose matches on Subject: below --
2022-05-01  6:06 [PATCH 0/3] Simplify ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA and revert aarch64/arm's extern protected data handling Fangrui Song
2022-05-01  6:06 ` [PATCH 2/3] Revert "[AArch64][BZ #17711] Fix extern protected data handling" Fangrui Song
2022-05-23 20:10   ` Szabolcs Nagy
2022-05-23 20:17     ` Fangrui Song
2022-05-24  5:13       ` Fangrui Song

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