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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/107754] Confusing -Warray-bounds warning with
 strcpy with a null pointer
Date: Fri, 18 Nov 2022 21:28:07 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107754

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2022-11-18
     Ever confirmed|0                           |1
            Summary|Confusing -Warray-bounds    |Confusing -Warray-bounds
                   |warning with strcpy         |warning with strcpy with a
                   |                            |null pointer
             Status|UNCONFIRMED                 |NEW

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed. Note the warning message is correct; just confusing and does not
mention a null pointer here.

Reduced further:
struct Foo
{
   unsigned int a;
   char bar[1024];
};
void setFoo(const char * value)
{
   struct Foo * ptr =3D 0;
   __builtin_strcpy(ptr->bar, value);
}


---- CUT ---
Since the offset for the character array is non-zero, we see a non-zero
constant and (based on other settings) assume it is the null pointer page a=
nd
we get a size of 0 (which is ok) but don't mention a null pointer.

There might be other dups of this but I am not going to search for it right
now.=