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From: Jonathan Wakely <jwakely.gcc@gmail.com>
Date: Tue, 16 Jun 2020 13:59:15 +0100
Message-ID: <CAH6eHdQ8WF0LVbDQQ-ZQCh29sNO3km-zyCkfX2P0950OZgoKmA@mail.gmail.com>
Subject: Re: Kind of undefined behavior (or bug?) with GCC 10.1
To: Roland Denis <denis@math.univ-lyon1.fr>
Cc: gcc-help <gcc-help@gcc.gnu.org>
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On Tue, 16 Jun 2020 at 12:58, Roland Denis wrote:
> Am I missing something important or does that look like a GCC bug ?

It's a bug. It started with https://gcc.gnu.org/r271510 and was fixed
in the master branch by https://gcc.gnu.org/r11-963 which was
addressing https://gcc.gnu.org/PR95493 which is a different bug.

> PS: result is correct with trunk version of GCC in godbolt, does that
> mean it is an already solved bug?

Looks like it, but I've added a comment to PR 95493 so that it can be
investigated and we can be sure your problem is really fixed.