https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95298
Bug ID: 95298 Summary: sorry, unimplemented: mangling record_type Product: gcc Version: 9.3.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: jonathan.poelen at gmail dot com Target Milestone: --- Since version 7 to trunk, the following code no longer compiles (https://godbolt.org/z/_j5EUA) template<class...> struct list{}; template<int n> struct _func_select { using f = void; }; struct func { template<class... seqs> using f = typename _func_select<sizeof...(seqs)>::f; }; template<class... T> func::f<list<T>...> foo(T&&...) {} int main() { foo(); }