It seems conceivable that a user would need to get a coroutine handle
having only a const reference to the promise_type, for example from
within a const member function of the promise.
This patch allows that use case. A coroutine_handle<const T> can be used
in essentially the same way a coroutine_handle<T>, ie to start and destroy
the coroutine. The constness of the promise doesn't/shouldn't propagate
to the handle.
llvm-svn: 305536
from_address requires that the provided pointer refer to the suspended coroutine,
which doesn't have a type, or at least not one knowable by the user. Therefore
every use of `from_address` with a typed pointer is almost certainly a bug.
This behavior is a part of the TS specification, but hopefully it will be
in the future.
llvm-svn: 304172
More tests to come. I think that from_address overload should be deleted
or ill-formed, except for the 'void*' one; The user cannot possibly
have a typed pointer to the coroutine state.
llvm-svn: 304131
Clang supports coroutines in all dialects; Therefore libc++ should too,
otherwise the Clang extension is unusable.
I'm not convinced extending support to C++03 is a feasible long term
plan, since as the library grows to offer things like generators it
will be come increasingly difficult to limit the implementation to C++03.
However for the time being supporting C++03 isn't a big deal.
llvm-svn: 303963
Clang started providing -fcoroutines and defining __cpp_coroutines
way before it implemented the __builtin_coro_foo functions. This
means that simply checking if __cpp_coroutines is not a sufficient
way of detecting the actual feature.
This patch implements _LIBCPP_HAS_NO_COROUTINES which implements
a slightly more complex feature check. Specifically it requires
__cpp_coroutines >= 201703L, which only holds for Clang 5.0 built
after 2017/05/24.
llvm-svn: 303956
The original issues were caused because <experimental/coroutine>
didn't correctly #ifdef out enough of the header, which caused incomplete
types to be used.
This patch fixes the `#if defined(__cpp_coroutines)` guard and re-adds
the headers to the module map.
It also uglifies some incorrectly non-reserved names.
llvm-svn: 303936
This patch updates the promise() member to match the current spec.
Specifically it removes the non-const overload and make the return
type of the const overload non-const.
This patch also makes the ASSERT_NOT_NOEXCEPT tests libc++ specific,
since other implementations may be free to strengthen the specification.
llvm-svn: 303895
Eric Fiselier