[clang] Surface error for plain return statement in coroutine earlier (PR #100985)

[via cfe-commits]

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@@ -291,6 +294,38 @@ void mixed_coreturn_template2(bool b, T) {
     return; // expected-error {{not allowed in coroutine}}
 }
 
+struct promise_handle;
+
+struct Handle : std::coroutine_handle<promise_handle> { // expected-note 2{{candidate constructor (the implicit copy constructor) not viable}}
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ivanaivanovska wrote:

Done.

https://github.com/llvm/llvm-project/pull/100985