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From: "janezz55 at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/109741] New: alignas(64) in
 libstdc++-v3/src/c++11/shared_ptr.cc
Date: Thu, 04 May 2023 17:30:35 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D109741

            Bug ID: 109741
           Summary: alignas(64) in libstdc++-v3/src/c++11/shared_ptr.cc
           Product: gcc
           Version: 13.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: janezz55 at gmail dot com
  Target Milestone: ---

This line:

struct alignas(64) M : __gnu_cxx::__mutex { };

has been an eyesore for me for a number of years. I propose to change it in=
to:

struct alignas(std::max_align_t) M : __gnu_cxx::__mutex { };

in which case <cstddef> needs to be #included as well. The magic number 64
alone should be raising some eyebrows and some targets do not support this
alignment.=