[PATCH] libstdc++, coroutine: Add missing constexpr markers.

[Jonathan Wakely]

On 17/07/20 10:05 +0100, Iain Sandoe wrote:
>Hi
>
>As per http://eel.is/c++draft/coroutine.trivial.awaitables the methods for
>the trivial awaitables are supposed to be constexpr.
>
>tested on x86_64-linux, darwin powerpc64-linux,
>OK for master?
>
>for 10.3?

OK for both, thanks.