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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/69482] Writing through pointers to volatile not
 always preserved
Date: Mon, 09 Jan 2023 11:46:15 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D69482

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |rguenth at gcc dot =
gnu.org

--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> ---
Note we do expand volatile qualified variables to memory but this case is a=
bout
non-volatile qualified variables stored to through volatile qualified point=
ers.
So it's

int foo (int i)
{
  volatile int j =3D i;
  return j;
}

vs.

int bar (int i)
{
  int j;
  *(volatile int *)&j =3D i;
  return j;
}

I have a patch.=