Implement <https://eel.is/c++draft/diff.cpp17.class#2>: template<class T> struct A { A<T>(); // error: simple-template-id not allowed for constructor A(int); // OK, injected-class-name used ~A<T>(); // error: simple-template-id not allowed for destructor }; Note this is not a DR against C++17, the above is only ill-formed in C++20 onwards.
Patch posted: <https://gcc.gnu.org/pipermail/gcc-patches/2020-April/543301.html>
Fixed in r11-532-g4b38d56dbac6742b038551a36ec80200313123a1.