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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/112666] Missed optimization: Value initialization
 zero-initializes members with user-defined constructor
Date: Thu, 23 Nov 2023 16:34:25 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D112666

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Francisco Paisana from comment #4)
> One last thing, I might have misread this as well.=20
>=20
> > "Zero-initialization is performed in the following situations:
> > ...
> > 2) As part of value-initialization sequence [...] for members of
> > value-initialized class types that have no constructors."
>=20
> I was interpreting it as "members that have no ctors of classes are
> zero-init".

I don't even know what that would mean.

> However, this could be also read as "members of classes, where
> the classes have no ctor, are zero-init."

This is the correct reading.

N.B. cppreference is not the standard. It's usually an accurate paraphrasin=
g of
the standard, but it's not gospel.=