gcc/testsuite/g++.dg/coroutines/torture/pr95519-03-return-value.C

//  { dg-do run }

#include "../coro.h"

struct pt_b
{
    std::suspend_never initial_suspend() const noexcept { return {}; }
    std::suspend_never final_suspend() const noexcept { return {}; }
    void unhandled_exception() const noexcept {}
};

int called_rv_op = 0;
int v;

struct pt_c : pt_b
{
  struct rv
    {
      void operator ()(int x){
        PRINTF("call to operator ret val with %d\n", x);
        called_rv_op++;
        v = x;
//      int val () { return x; }
    }
  };
  using handle_t = std::coroutine_handle<pt_c>;
  auto get_return_object() noexcept { return handle_t::from_promise(*this); }
  rv return_value;
};

int called_lambda = 0;

struct pt_d : pt_b
{
  using handle_t = std::coroutine_handle<pt_d>;
  auto get_return_object() noexcept { return handle_t::from_promise(*this); }
  static constexpr auto return_value
    = [] (int x) { PRINTF("call to lambda ret val %d\n", x); called_lambda++; v = x;};
};

template <> struct std::coroutine_traits<pt_c::handle_t>
    { using promise_type = pt_c; };

static pt_c::handle_t foo ()
{
    co_return 5;
}

template <> struct std::coroutine_traits<pt_d::handle_t>
    { using promise_type = pt_d; };

static pt_d::handle_t bar ()
{
    co_return 3;
}

int main ()
{
  /* These 'coroutines' run to completion imediately, like a regular fn.  */
  foo ();
  if (v != 5)
     {
      PRINT ("foo failed to set v");
      abort ();
    }

  bar ();
  if (v != 3)
     {
      PRINT ("bar failed to set v");
      abort ();
    }


  if (called_rv_op != 1 || called_lambda != 1)
    {
      PRINT ("Failed to call one of the return_value cases");
      abort ();
    }
}