gcc/testsuite/g++.dg/init/synth2.C

// PR c++/34180

struct G {
  G();
  G(G&);			// { dg-message "" "candidate" }
};

class A				// { dg-error "" }
{
  const G g;
};

int main()
{
  A a;
  A b = a;			// { dg-message "required here|deleted" }
}