Description

Hidden friends aren't hidden in C1XX's permissive mode, so let's use an alternate mechanism to make these operators truly ADL-only. (We want to avoid checking weakly_incrementable for every type that is compared via == or != with a type associated with namespace std.)

[This is a replay of Microsoft-internal MSVC-PR-216763.]

Checklist

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  or trivially copyable, etc.).
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  the C++ Working Draft (including any cited standards), other WG21 papers
  (excluding reference implementations outside of proposed standard wording),
  and LWG issues as reference material. If they were derived from a project
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