[PATCH] Implements DR 712 (odr-use, potential results of an expression)

Attached is an attempt to implement DR712 - please see the copied post at the end of the message for the general implementation strategy, and Richard smith’s initial guidance.

In regards to the testing, I test odr use through lambda capturing - I am not sure if this is the best way to test it - any guidance will be appreciated.

In my ODR use visitor:

  • am i correct in having the relevant traverses return false? I felt it was safe to abort, but am not certain.

  • do i need the empty VisitStmt?

  • do i need the constexpr check of the second operator of (s.*cexpr)?

DR712-odr-use-intial-submit.patch (16.7 KB)