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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug middle-end/104966] [11/12 Regression] Yet another bogus
 -Warray-bounds warning in libstdc++ headers
Date: Thu, 17 Mar 2022 12:46:36 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D104966

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
Well, the IL definitely has

 tem =3D operator new[] (0);
 /* some magic computing with 'positive_sign_size' */
 if (min (positive-sign-size, something) !=3D 0)
   if (__n =3D=3D 1)
     ;
   else
     {
       tem =3D __n * 4;
       if (tem !=3D 0)
         __builtin_memmove (dest, ..., tem);

so I guess that "magic" should always evaluate to 0 but we are not able
to figure that out despite the allocation being statically size zero.
You might be able to pin-point the libstdc++ piece with that magic?=