llvm-project/clang/test/SemaCXX/coroutine-seh.cpp
Chuanqi Xu ec117158a3 [Coroutines] [Frontend] Lookup in std namespace first
Now in libcxx and clang, all the coroutine components are defined in
std::experimental namespace.
And now the coroutine TS is merged into C++20. So in the working draft
like N4892, we could find the coroutine components is defined in std
namespace instead of std::experimental namespace.
And the coroutine support in clang seems to be relatively stable. So I
think it may be suitable to move the coroutine component into the
experiment namespace now.

This patch would make clang lookup coroutine_traits in std namespace
first. For the compatibility consideration, clang would lookup in
std::experimental namespace if it can't find definitions in std
namespace. So the existing codes wouldn't be break after update
compiler.

And in case the compiler found std::coroutine_traits and
std::experimental::coroutine_traits at the same time, it would emit an
error for it.

The support for looking up std::experimental::coroutine_traits would be
removed in Clang16.

Reviewed By: lxfind, Quuxplusone

Differential Revision: https://reviews.llvm.org/D108696
2021-11-04 11:53:47 +08:00

38 lines
1.2 KiB
C++

// RUN: %clang_cc1 -std=c++20 -verify %s -fcxx-exceptions -fexceptions -triple x86_64-windows-msvc -fms-extensions
namespace std {
template <typename... T> struct coroutine_traits;
template <class Promise = void> struct coroutine_handle {
coroutine_handle() = default;
static coroutine_handle from_address(void *) noexcept;
};
template <> struct coroutine_handle<void> {
static coroutine_handle from_address(void *) noexcept;
coroutine_handle() = default;
template <class PromiseType>
coroutine_handle(coroutine_handle<PromiseType>) noexcept;
};
} // namespace std
struct suspend_always {
bool await_ready() noexcept;
void await_suspend(std::coroutine_handle<>) noexcept;
void await_resume() noexcept;
};
template <> struct std::coroutine_traits<void> {
struct promise_type {
void get_return_object() noexcept;
suspend_always initial_suspend() noexcept;
suspend_always final_suspend() noexcept;
void return_void() noexcept;
void unhandled_exception() noexcept;
};
};
void SEH_used() {
__try { // expected-error {{cannot use SEH '__try' in a coroutine when C++ exceptions are enabled}}
co_return; // expected-note {{function is a coroutine due to use of 'co_return' here}}
} __except(0) {}
}