https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111019
--- Comment #4 from Sławomir Fraś <boskidialer at gmail dot com> --- Not sure if that hints at the possible cause, when i extracted `this` variable out of the loop to something like this (https://godbolt.org/z/8ebb5E1qG): Target* first = this; while (first->next) { Base* n = first->next; Then the code behaves the same as faulty code, but when i changed it into this (https://godbolt.org/z/7o58Y4fEq): Base* first = this; // only change: Target -> Base while (first->next) { Base* n = first->next; Then the code works fine even with the `always_inline` on the destructor. In this case it looks like write to `Base::next` member is not considered as invalidating value of `Target::next` in register even when it should since Target derives from the Base class.
