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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/58483] missing optimization opportunity for
 const std::vector compared to std::array
Date: Tue, 30 May 2023 18:43:55 +0000
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X-Bugzilla-Component: tree-optimization
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X-Bugzilla-Keywords: missed-optimization
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D58483

--- Comment #17 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Here is related reduced testcase:
```

int f(void)
{
        int tt =3D 100;
        int t[3] =3D {10,20,30};
        int *t1 =3D new int[3];
        __builtin_memcpy(t1, t, sizeof(t));
        for(int *i =3D t1; i !=3D &t1[3]; i++)
          tt +=3D *i;
        delete[] t1;
        return tt;
}
```
Note in the above testcase we can remove the memcpy but not the operator
new/delete.  This is unlike the original testcase where memcpy is not remov=
ed
either.=