Issue 11286 - Impure dtor makes "cannot call impure function" error, although it won't actually be called.

[9rnsr]

http://d.puremagic.com/issues/show_bug.cgi?id=11286

[monarchdodra]

I left a question here:
http://d.puremagic.com/issues/show_bug.cgi?id=11287#c1

Basically, if we allow:

A getA() pure
{
    A a;        // line 7
    return a;   // NRVO
}

Doesn't that make NRVO a mandatory optimization? Wouldn't this be a problem?

[DmitryOlshansky]

Doesn't that make NRVO a mandatory optimization? Wouldn't this be a problem?

It would be real nice in fact :) Finally everyone can absolutely count on it being done.

[9rnsr]

I replied in bugzilla: http://d.puremagic.com/issues/show_bug.cgi?id=11287#c2

In 2.064 development, all of NRVO handling were moved in front-end. So now it is testable in compile-time except the case in bug 11287.

I also think NRVO is one of the importand dmd feature, and the D specification should mention about it, because "create an object and move it to the caller" is necessary feature to extend the returned object lifetime.

[Dgame]

@WalterBright can this be merged?