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<p class="MsoNormal">Hello, <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Clang throws an error on Windows when I try to compile the following test.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">ksh-3.2$ cat test.cpp<o:p></o:p></p>
<p class="MsoNormal">#include <coroutine><o:p></o:p></p>
<p class="MsoNormal">#include <iostream><o:p></o:p></p>
<p class="MsoNormal">using namespace std;<o:p></o:p></p>
<p class="MsoNormal">using std::coroutine_handle;<o:p></o:p></p>
<p class="MsoNormal">using std::suspend_always;<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">ksh-3.2$ clang-cl -c /std:c++latest test.cpp<o:p></o:p></p>
<p class="MsoNormal">test2.cpp(4,12): error: no member named 'coroutine_handle' in namespace 'std'<o:p></o:p></p>
<p class="MsoNormal">using std::coroutine_handle;<o:p></o:p></p>
<p class="MsoNormal"> ~~~~~^<o:p></o:p></p>
<p class="MsoNormal">test2.cpp(5,12): error: no member named 'suspend_always' in namespace 'std'<o:p></o:p></p>
<p class="MsoNormal">using std::suspend_always;<o:p></o:p></p>
<p class="MsoNormal"> ~~~~~^<o:p></o:p></p>
<p class="MsoNormal">2 errors generated.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I noticed the STL implementation (<a href="https://github.com/microsoft/STL/blob/master/stl/inc/coroutine#L16">https://github.com/microsoft/STL/blob/master/stl/inc/coroutine#L16</a>) was guarded with __cpp_lib_coroutine. So I tried clang-cl
-c /std:c++latest -D__cpp_lib_coroutine test.cpp and the header successfully compiled.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">From <a href="https://github.com/microsoft/STL/issues/1223">
https://github.com/microsoft/STL/issues/1223</a>, it looks like the errors are a known issue. __cpp_lib_coroutine will be defined by library only if compiler defines __cpp_impl_coroutine. I assume clang doesn’t define the feature test macro because we lack
sufficient coroutine support. Would someone here be able to confirm? <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Also, if anyone has information about current status of coroutine support/what is missing, any help is greatly appreciated.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thank you, <o:p></o:p></p>
<p class="MsoNormal">Elizabeth<o:p></o:p></p>
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