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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug tree-optimization/105651] bogus "may overlap" memcpy warning
 with std::string
Date: Thu, 19 May 2022 00:10:15 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105651

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|c++                         |tree-optimization
      Known to fail|                            |11.1.0, 12.1.0, 13.0
            Summary|Failure compiling           |bogus "may overlap" memcpy
                   |constexpr/__builtin_memcpy  |warning with std::string
                   |on Cygwin with -std=3Dc++20   |
             Target|                            |x86_64-pc-cygwin
           Keywords|                            |diagnostic

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
> Builds on gcc-11,12,13 with -std=3Dc++17, but all three fail with c++20.

std::string changes slightly with C++20 and IIRC more inlining happens whic=
h is
why the warning happens only with -std=3Dc++20.=