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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/110714] constexpr lifetime error: base class this pointer
Date: Fri, 22 Mar 2024 00:53:46 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110714

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|2023-07-18 00:00:00         |2024-3-22

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I encountered this using std::pointer_traits<P>::pointer_to in constexpr co=
de
like so:

#include <memory>

struct B { constexpr virtual ~B() =3D default; };
struct D : B { };

consteval void f()
{
  delete std::pointer_traits<B*>::pointer_to(*new D());
}

int main()
{
  f();
}


Which can be simplified to:

struct B { constexpr virtual ~B() =3D default; };
struct D : B { };

consteval void f()
{
  delete &(B&)*new D();
}

int main()
{
  f();
}=