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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/105523] Wrong warning array subscript [0] is outside
 array bounds
Date: Tue, 25 Apr 2023 17:04:07 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105523

--- Comment #28 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Wilhelm M from comment #26)
> As you can see in my opening bug report, there is no nullptr reference nor
> dereferencing a pointer with value 0.

Yes but as I mentioned by the time the warning happens, the IR has lost
information if the constant came from a null pointer or from some other
constant that the user used. So a heuristic needs to be used and the idea w=
as
it would be the lower bytes by default and that the lower bytes would be
defined by a "page size" and that is how the naming of the option happened.=