gcc/testsuite/g++.dg/lookup/koenig14.C

   1 // ADL can be recursive (via instantiation), make sure that works.
   2
   3 namespace X
   4 {
   5   class B {};
   6
   7   void frob ();
   8   int frob (B); // Inner ADL resolves here
   9 }
  10
  11 void frob (int);
  12 void frob (float);
  13
  14 namespace Y
  15 {
  16   struct A {};
  17   void frob (void*, void *, void *); // Outer ADL resolves here
  18 }
  19
  20 template <typename T, typename U>
  21 struct C : U
  22 {
  23   int ary[sizeof frob(T())]; // ADL occurs here during instantiation
  24 };
  25
  26 void Foo (C<X::B, Y::A> *p, X::B *q)
  27 {
  28   frob(q, p, q); // ADL causes instantation of C<...>
  29   // We will have already searched X by the time the instantation happens
  30 }