https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109770
m.cencora at gmail dot com changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |m.cencora at gmail dot com
--- Comment #6 from m.cencora at gmail dot com ---
(In reply to Richard Biener from comment #0)
> #include <new>
>
> struct Base
> {
> virtual ~Base() {}
> };
> struct A : Base
> {
> virtual ~A() {}
> };
> struct B : Base
> {
> [[gnu::noinline]] B() { new (this) A; }
> virtual ~B() { __builtin_abort (); }
> };
> int main()
> {
> Base *p = new B;
> delete p;
> }
>
> aborts when compiled with -O2 (with devirtualization enabled). Neither
> GCC nor clang diagnose the placement new in B::B() (but it looks fishy).
I believe you need to std::launder the p pointer before calling delete:
https://en.cppreference.com/w/cpp/utility/launder
