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From: "qinzhao at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/109071] -Warray-bounds false positive
 warnings due to code duplication from jump threading
Date: Mon, 22 Apr 2024 20:04:45 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D109071

--- Comment #7 from qinzhao at gcc dot gnu.org ---
(In reply to Kees Cook from comment #6)
> (In reply to qinzhao from comment #5)
> > adding __attribute__ ((noreturn)) to the routine "warn" can eliminate t=
he
> > false positive warning.
>=20
> But it does return... it's not an assert.

***the original code is:

if (index >=3D 4)
  warn ();
*regs =3D sg->vals[index];

if the routine "warn" does return, then
it's reasonable to convert the above original code to:

***the transformed code:

if (index >=3D 4)
  {
    warn ();
    *regs =3D sg->vals[index];   /* here, index >=3D 4, therefore, out-of-b=
ound */
  }
else
  *regs =3D sg->vals[index];=