1 // PR c++/44625
2 // { dg-do compile }
3 // { dg-options "" }
4 // { dg-additional-options "-Wno-return-type" }
5 
6 template<typename FP_> struct Vec { // { dg-message "note" "" { target c++17_down } }
7     Vec& operator^=(Vec& rhs)     {
8         union {
9             struct {FP_ x,y,z;}; // { dg-error "20:anonymous struct" }
10         };
11         X = y*rhs.z() - z*rhs.y(); // { dg-error "not declared|no member" }
12     }
13     Vec& operator^(Vec& rhs) {
14         return Vec(*this)^=rhs; // { dg-message "required" }
15     }
16 };
17 Vec<double> v(3,4,12); // { dg-error "no matching|too many initializers" }
18 Vec<double> V(12,4,3);  // { dg-error "no matching|too many initializers" }
19 Vec<double> c = v^V;   // { dg-message "required" }
20