gcc/testsuite/g++.dg/cpp1z/inh-ctor22.C

   1 // Testcase from P0136
   2 // { dg-do compile { target c++11 } }
   3
   4 struct B1 {
   5   template <class... Ts>
   6   B1(int, Ts...) { }
   7 };
   8
   9 struct B2 {
  10   B2(double) { }
  11 };
  12
  13 int get();
  14
  15 struct D1 : B1 {                // { dg-message "B1::B1" }
  16   using B1::B1;  // inherits B1(int, ...)
  17   int x;
  18   int y = get();
  19 };
  20
  21 void test() {
  22   D1 d(2, 3, 4); // OK: B1 is initialized by calling B1(2, 3, 4),
  23   // then d.x is default-initialized (no initialization is performed),
  24   // then d.y is initialized by calling get()
  25   D1 e;          // { dg-error "" } D1 has a deleted default constructor
  26 }
  27
  28 struct D2 : B2 {
  29   using B2::B2;                 // { dg-message "B1::B1" }
  30   B1 b;
  31 };
  32
  33 D2 f(1.0);       // { dg-error "" } B1 has no default constructor