• via Digitalmars-d-bugs (28/28) May 31 2017 https://issues.dlang.org/show_bug.cgi?id=17457

via Digitalmars-d-bugs <digitalmars-d-bugs puremagic.com> writes:

https://issues.dlang.org/show_bug.cgi?id=17457

          Issue ID: 17457
           Summary: Named Return Value Optimization (NRVO) not done with
                    return of constructor call
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody puremagic.com
          Reporter: bugzilla digitalmars.com

NRVO is not done for:

  struct S {
    ulong[10] x; // ensure stack placement instead of register placement
    this(int i);
  }

  S foo() {
    return S(10);
  }

but is done for:

  S foo() {
    auto s = S(10);
    return s;
  }

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