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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/108217] bogus -Warray-bounds with pointer to constant local
Date: Sat, 24 Dec 2022 20:42:12 +0000	[thread overview]
Message-ID: <bug-108217-4-FUZt4eQXum@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-108217-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108217

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The problem with const is GCC does not have an idea of a store once and then
become constant.
an example of that would be:
```
void ExternFunc(const int*);

int f();

int Bad() {
  const int i = f();
  const int* pi = &i;
  ExternFunc(pi);
  return *pi;
}

int Good() {
  const int i = f();
  ExternFunc(&i);
  return i;
}
```
This is similar to LLVM/clang really because this does not come up that much.

  parent reply	other threads:[~2022-12-24 20:42 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-12-24 10:53 [Bug middle-end/108217] New: " jhaberman at gmail dot com
2022-12-24 20:11 ` [Bug middle-end/108217] " pinskia at gcc dot gnu.org
2022-12-24 20:14 ` pinskia at gcc dot gnu.org
2022-12-24 20:35 ` jhaberman at gmail dot com
2022-12-24 20:42 ` pinskia at gcc dot gnu.org [this message]
2022-12-24 20:46 ` pinskia at gcc dot gnu.org

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