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From:   Florian Weimer <fweimer@redhat.com>
To:     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc:     Chris Kennelly <ckennelly@google.com>,
        Paul Turner <pjt@google.com>, Peter Oskolkov <posk@posk.io>,
        libc-alpha <libc-alpha@sourceware.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>
Subject: Re: Aligning tcmalloc with glibc 2.35 rseq ABI
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Date:   Wed, 02 Feb 2022 16:01:15 +0100
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        (Mathieu Desnoyers's message of "Wed, 2 Feb 2022 08:08:55 -0500
        (EST)")
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* Mathieu Desnoyers:

> More to the point: is ptrdiff_t the correct type here ? I think so.
> Do we want to revert the ABI and wait another 6 months before we
> bring back rseq into glibc just for this ? I'm not sure this limitation
> justifies it.
>
> So if there is a quick way to fix that before the official 2.35 release,
> I'm all for it, otherwise I cannot say that __rseq_offset being an "int"
> rather than a "ptrdiff_t" will make much real-life difference (unless
> I'm proven wrong). But we will be stuck with this quirk forever.

I'm going to post a patch.  It's fairly small.

Thanks,
Florian