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From: Jan Beulich <jbeulich@suse.com>
To: "H.J. Lu" <hjl.tools@gmail.com>
Cc: binutils@sourceware.org
Subject: Re: [PATCH] i386: Allow GOT32 relocations against ABS symbols
Date: Tue, 8 Feb 2022 09:37:28 +0100	[thread overview]
Message-ID: <4785d6f1-cd0c-2ad4-9a13-6a05f6557b69@suse.com> (raw)
In-Reply-To: <20220208000322.4108601-1-hjl.tools@gmail.com>

On 08.02.2022 01:03, H.J. Lu via Binutils wrote:
> GOT32 relocations are allowed since absolute value + addend is stored in
> the GOT slot.

Before permitting this and with you specifically mentioning addends
here, I think it needs to be clarified what ...

> --- /dev/null
> +++ b/ld/testsuite/ld-i386/pr28870.s
> @@ -0,0 +1,6 @@
> +	.text
> +	.globl _start
> +_start:
> +	addl	foo@GOT(%ebx), %eax
> +	cmpl	$0, foo@GOT(%ebx)
> +foo = 2

... missing (here) variants thereof actually mean (and whether the use
of addends actually works as intended):

	mov	$v@got+3, %eax				# bogus, meaningless operand
	mov	$(v+3)@got, %eax			# wrong (gets treated same as above)

Comments are my own, preliminary judgement.

Jan


  reply	other threads:[~2022-02-08  8:37 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-02-08  0:03 H.J. Lu
2022-02-08  8:37 ` Jan Beulich [this message]
2022-02-08 13:02   ` H.J. Lu
2022-02-08 13:10     ` Jan Beulich
2022-02-08 13:20       ` H.J. Lu

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