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* [Bug rtl-optimization/70889] memory reordering across loads tagged as memory_order_seq_cst
       [not found] <bug-70889-4@http.gcc.gnu.org/bugzilla/>
@ 2021-08-22 19:42 ` pinskia at gcc dot gnu.org
  2021-08-22 20:04 ` pinskia at gcc dot gnu.org
  1 sibling, 0 replies; 2+ messages in thread
From: pinskia at gcc dot gnu.org @ 2021-08-22 19:42 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70889

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Testcase:

#include <atomic>
#include <iostream>

std::atomic<std::size_t> seq_;
std::size_t value;

auto load()
{
    std::size_t copy;
    std::size_t seq0;
    do
    {
        seq0 = seq_.load();
        if (!seq0) continue;
        copy = value;
        seq0 = seq_.load();
    } while (!seq0);

    return copy;
}

^ permalink raw reply	[flat|nested] 2+ messages in thread

* [Bug rtl-optimization/70889] memory reordering across loads tagged as memory_order_seq_cst
       [not found] <bug-70889-4@http.gcc.gnu.org/bugzilla/>
  2021-08-22 19:42 ` [Bug rtl-optimization/70889] memory reordering across loads tagged as memory_order_seq_cst pinskia at gcc dot gnu.org
@ 2021-08-22 20:04 ` pinskia at gcc dot gnu.org
  1 sibling, 0 replies; 2+ messages in thread
From: pinskia at gcc dot gnu.org @ 2021-08-22 20:04 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70889

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |DUPLICATE

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Dup of bug 57448 which is fixed in GCC 8.

*** This bug has been marked as a duplicate of bug 57448 ***

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2021-08-22 20:04 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
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     [not found] <bug-70889-4@http.gcc.gnu.org/bugzilla/>
2021-08-22 19:42 ` [Bug rtl-optimization/70889] memory reordering across loads tagged as memory_order_seq_cst pinskia at gcc dot gnu.org
2021-08-22 20:04 ` pinskia at gcc dot gnu.org

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