clang/test/PCH/coroutines.cpp

   1 // Test this without pch.
   2 // RUN: %clang_cc1 -include %s -verify -std=c++20 %s
   3
   4 // Test with pch.
   5 // RUN: %clang_cc1 -std=c++20  -emit-pch -o %t %s
   6 // RUN: %clang_cc1 -include-pch %t -verify -std=c++20 %s
   7
   8 #ifndef HEADER
   9 #define HEADER
  10
  11 namespace std {
  12 template <typename... T> struct coroutine_traits;
  13
  14 template <class Promise = void> struct coroutine_handle {
  15   coroutine_handle() = default;
  16   static coroutine_handle from_address(void *) noexcept;
  17 };
  18 template <> struct coroutine_handle<void> {
  19   static coroutine_handle from_address(void *) noexcept;
  20   coroutine_handle() = default;
  21   template <class PromiseType>
  22   coroutine_handle(coroutine_handle<PromiseType>) noexcept;
  23 };
  24 } // namespace std
  25
  26 struct suspend_always {
  27   bool await_ready() noexcept;
  28   void await_suspend(std::coroutine_handle<>) noexcept;
  29   void await_resume() noexcept;
  30 };
  31
  32 template <typename... Args> struct std::coroutine_traits<void, Args...> {
  33   struct promise_type {
  34     void get_return_object() noexcept;
  35     suspend_always initial_suspend() noexcept;
  36     suspend_always final_suspend() noexcept;
  37     void return_void() noexcept;
  38     suspend_always yield_value(int) noexcept;
  39     promise_type();
  40     ~promise_type() noexcept;
  41     void unhandled_exception() noexcept;
  42   };
  43 };
  44
  45 template <typename... Args> struct std::coroutine_traits<int, Args...> {
  46   struct promise_type {
  47     int get_return_object() noexcept;
  48     suspend_always initial_suspend() noexcept;
  49     suspend_always final_suspend() noexcept;
  50     void return_value(int) noexcept;
  51     promise_type();
  52     ~promise_type() noexcept;
  53     void unhandled_exception() noexcept;
  54   };
  55 };
  56
  57 template <typename T>
  58 void f(T x) {  // checks coawait_expr and coroutine_body_stmt
  59   co_yield 42; // checks coyield_expr
  60   co_await x;  // checks dependent_coawait
  61   co_return;   // checks coreturn_stmt
  62 }
  63
  64 template <typename T>
  65 int f2(T x) {  // checks coawait_expr and coroutine_body_stmt
  66   co_return x;   // checks coreturn_stmt with expr
  67 }
  68
  69 struct S {};
  70 S operator co_await(S) { return S(); }
  71
  72 template <typename T>
  73 int f3(T x) {
  74   co_await x; // checks dependent_coawait with overloaded co_await operator
  75 }
  76
  77 #else
  78
  79 // expected-no-diagnostics
  80 void g() {
  81   f(suspend_always{});
  82   f2(42);
  83 }
  84
  85 #endif