From: Michael Matz <matz@suse.de>
To: "Richard Earnshaw (lists)" <Richard.Earnshaw@arm.com>
Cc: binutils@sourceware.org
Subject: Re: [PATCH] PR30437 aarch64: make RELA relocs idempotent
Date: Thu, 25 May 2023 16:01:47 +0000 (UTC) [thread overview]
Message-ID: <alpine.LSU.2.20.2305251559490.13548@wotan.suse.de> (raw)
In-Reply-To: <57db6134-6543-0763-62de-bb70208e766f@arm.com>
Hello,
On Thu, 25 May 2023, Richard Earnshaw (lists) wrote:
> > (And of course, it's always possible that REL relocations cannot always be
> > used to achieve idempotence even in presence of 'ld -r', in which case
> > RELA must be used. The aarch64 psABI thankfully even spells this out.)
>
> There's no fundamental reason why a toolchain doing 'ld -r' can't always emit
> RELA format relocs, even if the input format was REL. In fact, I'd argue that
> really it has to in most cases as 'ld -r' destroys the information that's
> needed to reprocess the relocations.
Right.
> But I agree with you, this is all likely broken in BFD because we have
> no way of testing it (gas can't create multiple relocs to a single
> location to the best of my knowledge).
With the .reloc directive it should be possible. But if you try to do
that you probably go down a rabbit hole of strange and wonderful
proportions :)
Ciao,
Michael.
next prev parent reply other threads:[~2023-05-25 16:01 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-05-10 14:04 Michael Matz
2023-05-17 14:35 ` Nick Clifton
2023-05-24 15:26 ` Richard Earnshaw (lists)
2023-05-24 16:03 ` Michael Matz
2023-05-25 9:35 ` Richard Earnshaw (lists)
2023-05-25 12:29 ` Michael Matz
2023-05-25 13:22 ` Richard Earnshaw (lists)
2023-05-25 14:12 ` Michael Matz
2023-05-25 15:56 ` Richard Earnshaw (lists)
2023-05-25 16:01 ` Michael Matz [this message]
2023-05-24 22:54 ` Alan Modra
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