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From: "jamrial at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/59767] __atomic_load_n with __ATOMIC_SEQ_CST should result in a memory barrier
Date: Thu, 02 Jul 2015 16:35:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59767

James Almer <jamrial at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jamrial at gmail dot com

--- Comment #1 from James Almer <jamrial at gmail dot com> ---
This still happens with gcc 4.9 and gcc 5.

int foo(int *bar)
{
    return *bar;
}

and

int foo(int *bar)
{
    return __atomic_load_n(bar, __ATOMIC_SEQ_CST);
}

Generate the exact same assembly. The latter should add an mfence before the
mov instruction.