| // { dg-do compile } | |
| // { dg-require-effective-target c++17 } | |
| // { dg-options "-O -Wuninitialized" } | |
| #include <optional> | |
| struct X { | |
| X() = default; | |
| X(X const& r) : i(r.i) {} | |
| int i; | |
| }; | |
| struct Y { | |
| Y() : x() {} | |
| X x; | |
| std::optional<int> o; | |
| }; | |
| struct Z { | |
| Y y; | |
| explicit Z(Y y) : y(y) {} | |
| }; | |
| void f(Y const&); | |
| void test() { | |
| Y const y; | |
| Z z(y); | |
| z.y.o = 1; | |
| auto const w = z; | |
| f(w.y); | |
| } |