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[class.copy.elision] Is the first example contradictory? #3117

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frederick-vs-ja opened this issue Aug 2, 2019 · 1 comment · Fixed by #3254
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[class.copy.elision] Is the first example contradictory? #3117

frederick-vs-ja opened this issue Aug 2, 2019 · 1 comment · Fixed by #3254
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@frederick-vs-ja
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(In N4820) The first example says that

struct A {
  void *p;
  constexpr A(): p(this) {}
};

constexpr A g() {
  A a;
  return a;
}

constexpr A a;          // well-formed, a.p points to a
constexpr A b = g();    // well-formed, b.p points to b

However, if my understanding is correct, as copy elision (NRVO) is forbidden in constant initialization since CWG 2278, b.p shall point to the local variable a in g whose lifetime has ended.
@jensmaurer jensmaurer added the decision-required A decision of the editorial group (or the Project Editor) is required. label Aug 6, 2019
@jensmaurer jensmaurer added decision-required A decision of the editorial group (or the Project Editor) is required. and removed decision-required A decision of the editorial group (or the Project Editor) is required. labels Sep 10, 2019
@jensmaurer jensmaurer removed the decision-required A decision of the editorial group (or the Project Editor) is required. label Sep 30, 2019
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Editorial teleconference: Agreed, this is an error in second line of the example. Also change name of local variable "a" to avoid duplication of name.

@frederick-vs-ja frederick-vs-ja mentioned this issue Oct 1, 2019
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[class.copy.elision] Fix the contradiction introduced by CWG 2278
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