https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106366
Patrick Palka <ppalka at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Ever confirmed|0 |1 Assignee|unassigned at gcc dot gnu.org |ppalka at gcc dot gnu.org CC| |ppalka at gcc dot gnu.org Keywords| |rejects-valid Status|UNCONFIRMED |ASSIGNED Last reconfirmed| |2022-07-20 --- Comment #1 from Patrick Palka <ppalka at gcc dot gnu.org> --- Confirmed, reduced: #include <initializer_list> template<class T> struct A { A(...); }; template<class T> A(std::initializer_list<T>) -> A<T>; A a{1,2,3}; This seems valid according to [over.match.class.deduct]/4. In order for the initializer-list phase of overload resolution to kick in the class template doesn't necessarily need an initializer-list constructor, it suffices to just have a guide that looks like one.