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From:   Andreas Schwab <schwab@linux-m68k.org>
To:     Jessica Clarke <jrtc27@jrtc27.com>
Cc:     Changbin Du <changbin.du@gmail.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        linux-riscv <linux-riscv@lists.infradead.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] riscv: eliminate unreliable __builtin_frame_address(1)
References: <20220117154433.3124-1-changbin.du@gmail.com>
        <C2470F2D-9E45-49D7-A03B-E6A7BB4B9738@jrtc27.com>
Date:   Wed, 19 Jan 2022 11:58:04 +0100
In-Reply-To: <C2470F2D-9E45-49D7-A03B-E6A7BB4B9738@jrtc27.com> (Jessica
        Clarke's message of "Mon, 17 Jan 2022 17:33:40 +0000")
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On Jan 17 2022, Jessica Clarke wrote:

> Yes, this is a bug, that is always wrong. LLVM gets this right.

Is that an ABI requirement?  In case of a leaf function, gcc saves the
caller's frame pointer in the first slot, not the second (it doesn't
save the return address).

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510  2552 DF73 E780 A9DA AEC1
"And now for something completely different."