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Date: Thu, 6 Jan 2022 18:01:30 -0800
From: Fangrui Song <i@maskray.me>
To: Alan Modra <amodra@gmail.com>
Cc: "H.J. Lu" <hjl.tools@gmail.com>, binutils@sourceware.org,
 Cary Coutant <ccoutant@gmail.com>
Subject: Re: DT_RELR design
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On 2022-01-07, Alan Modra via Binutils wrote:
>gcc -shared -fPIC on the following
>struct pack { char c; void *p; } __attribute__ ((__packed__));
>static char x;
>struct pack ref = { 'A', &x };
>
>results in
>0000000000004021  0000000000000008 R_X86_64_RELATIVE
>
>That odd address can't be encoded by the current DT_RELR design.
>That's likely to cause you some trouble on x86.

Odd addresses use R_*_RELATIVE.
Even addresses use .relr.dyn.

In my gold patch
https://sourceware.org/pipermail/binutils/2021-November/118567.html
gold/testsuite/relr_aarch64.sh actually tests this.