https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109405
Bug ID: 109405
Summary: Should class final decoration result in larger
unique_ptr with deleter ?
Product: gcc
Version: 13.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: gcc at hazlewoods dot net
Target Milestone: ---
Whilst making an attempt to ensure some `std::unique_ptr<>` types had size
`sizeof(intptr_t)`, I was using empty `struct` deleters.
I habitually tapped `final` on a struct, and was surprised to see my
`static_assert`s fire.
Maybe this is a consequence of the push for devirtualization optimization, but
hopefully this can be confirmed.
```
#include <iostream>
#include <memory>
int main()
{
struct S { void operator()() {} };
struct SF final { void operator()() {} };
std::cout << "S : " << sizeof(S) << std::endl;
std::cout << "SF: " << sizeof(SF) << std::endl;
using SP = std::unique_ptr<int, S>;
using SFP = std::unique_ptr<int, SF>;
std::cout << "SP : " << sizeof(SP) << std::endl;
std::cout << "SFP: " << sizeof(SFP) << std::endl;
}
```
https://godbolt.org/z/Gfz4W5sP1
