https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99185
--- Comment #6 from m.cencora at gmail dot com --- Now that I think about and having read relevant chapters of C++20 spec, observed behavior seems to be expected. A cannot be constant initialized (because it has missing initializer for 'value' member) so at first zero-initialization is performed as part of static initialization, then A constructor is called as part of dynamic initialization.
