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From: "wilco at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/110773] [Aarch64] crash (SIGBUS) due to atomic
 instructions on under-aligned memory
Date: Thu, 07 Sep 2023 14:38:55 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110773

Wilco <wilco at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |wilco at gcc dot gnu.org

--- Comment #2 from Wilco <wilco at gcc dot gnu.org> ---
This is really a user error, not a compiler issue. Just write it like:

struct Storage {
    std::atomic<FloatPair> fp1;
    float padding;
    std::atomic<FloatPair> fp2;
} storage;

This ensures the correct alignment required for atomic accesses of fp1/fp2.=