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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/114768] Volatile reads can be optimized away
Date: Thu, 18 Apr 2024 13:21:22 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114768

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
It's the combine pass that removes the seemingly noop-move.

For QOI reasons GCC preserves volatile accesses elsewhere even when
inconsistency is directly visible like here.=