On 04/08/2016 02:39 PM, Hans Boehm wrote:
My prior impression was that Opaque was intended to be similar to a C++ memory_order_relaxed access to a variable that is declared as both atomic and volatile, with the unordered interpretation of C++ "volatile".
Yes. This is awkward to spell out in detail, but surely there is some way to say it that is more illuminating than confusing. Especially since the implementation on all known processors is straightforward -- reading/writing (all bits atomically) in program order. -Doug