Just to be clear, the appended 17 lines of very simple code breaks gcc
on every platform where <coroutine> header does not have <new> in its
include hierarchy....which I assume to be every platform.
1) place code below in main.cpp
2) g++ -std=c++20 main.cpp
and you get
main.cxx: In function 'my_co do_co()':
main.cxx:16:7: error:
'my_co::promise_type::get_return_object_on_allocation_failure()' is
provided by 'std::__n4861::__coroutine_traits_impl<my_co,
void>::promise_type' {aka 'my_co::promise_type'} but *'std::nothrow'
cannot be found*
16 | my_co do_co() { co_return; }
| ^~~~~
Here's the code:
// begin code --------------------------------
#include <coroutine>
struct my_co {
struct promise_type {
static my_co get_return_object_on_allocation_failure() {
return my_co(); }
my_co get_return_object() { return my_co(); }
std::suspend_always initial_suspend() noexcept { return {}; }
std::suspend_always final_suspend() noexcept { return {}; }
void return_void() {}
void unhandled_exception() {}
};
};
my_co do_co() { co_return; }
int main()
{
do_co();
return 0;
}
// end code ----------------------------
