[Concurrency] Evolving the Concurrency design and proposals

[Michael_Ilseman]

@Douglas_Gregor

Banning overloading of async and synchronous methods that otherwise have the same signature (but see the below about overload resolution).
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We are not inclined to eliminate the overload-resolution rule that prefers async in asynchronous contexts and synchronous functions in synchronous contexts.

If we ban overloading, then what situation does this overload-resolution rule apply to? Would this be Clang importer magic or am I misunderstanding the change? Would the overload-resolution rule interact with implicit promotion to async (it that is ever added)?