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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/112307] Segmentation fault with -O1
 -fcode-hoisting
Date: Tue, 05 Mar 2024 11:34:43 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D112307

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |redi at gcc dot gnu.org

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
I don't quite see how

  return EnumeratorRange(Enumerator(std::views::single(Intersection())));

makes CompositeMesh::Intersections() return an object that refers to itself
but points-to doesn't consider it could:

callarg(12) =3D &mesh
...
ESCAPED =3D &mesh
intersections =3D NONLOCAL
intersections =3D callarg(12)

debugging at -O0 shows

(gdb) p intersections
$1 =3D {enumerator_ =3D {
    range_ =3D
{<std::ranges::view_interface<std::ranges::single_view<Intersection> >> =3D=
 {<No
data fields>}, _M_value =3D {_M_value =3D {is_boundary_ =3D true}}},=20
    begin_ =3D std::optional<Intersection *> =3D {
      [contained value] =3D 0x7fffffffde80}}, end_reached_ =3D false}
(gdb) p &intersections
$2 =3D (EnumeratorRange<CompositeMesh::Intersections() const::Enumerator> *)
0x7fffffffde80

so it contains a reference to itself.  As said this feels like those other
issues which are maybe invalid because of object lifetimes.

But maybe there's sth special here.=