1 // { dg-do compile { target c++11 } } 2 3 struct A 4 { 5 constexpr operator double() { return 1.0; } 6 }; 7 8 template <int I> 9 struct B 10 { }; 11 12 constexpr A a { }; 13 B<a> b; // { dg-error "template argument|converted constant|could not convert" } 14