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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/106020] Spurious warnings about stringop
 overflows with -march=skylake -O3
Date: Thu, 18 May 2023 03:29:40 +0000
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X-Bugzilla-Component: tree-optimization
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D106020

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|lto                         |

--- Comment #9 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Reduced much further (still has includes):
```
#include <limits>
#include <algorithm>
void f(const char*);
typedef char CharT;
void read(unsigned u)
{
        CharT buf[std::numeric_limits<unsigned>::digits10+2u] =3D {};
        CharT* e =3D buf;
        do
        {
            *e++ =3D static_cast<CharT>(CharT(u % 10) + CharT{'0'});
            u /=3D 10;
        } while (u > 0);
        e[0] =3D 0;
        std::reverse(buf, e);
        f(buf);
}
```
Just compile with `-std=3Dc++20 -O3 -march=3Dskylake` is enough to get the =
warning.=