From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
 id DF05D39960F5; Thu,  5 Aug 2021 11:39:39 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org DF05D39960F5
From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/101780] Missing initializers whereas structure has default
 initializers
Date: Thu, 05 Aug 2021 11:39:39 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: c++
X-Bugzilla-Version: 11.2.0
X-Bugzilla-Keywords: diagnostic
X-Bugzilla-Severity: normal
X-Bugzilla-Who: redi at gcc dot gnu.org
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: 
Message-ID: <bug-101780-4-LWl4lEJ0BR@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-101780-4@http.gcc.gnu.org/bugzilla/>
References: <bug-101780-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-BeenThere: gcc-bugs@gcc.gnu.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Gcc-bugs mailing list <gcc-bugs.gcc.gnu.org>
List-Unsubscribe: <https://gcc.gnu.org/mailman/options/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=unsubscribe>
List-Archive: <https://gcc.gnu.org/pipermail/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-request@gcc.gnu.org?subject=help>
List-Subscribe: <https://gcc.gnu.org/mailman/listinfo/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=subscribe>
X-List-Received-Date: Thu, 05 Aug 2021 11:39:40 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101780

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to KL from comment #0)
> Can you confirm it is the intended behavior?

See the documentation for -Wmissing-field-initializers.

It doesn't warn about members being uninitialized, it warns about them not
being explicitly initialized, which is the case here.

The manual does say it doesn't warn about designated initializers, but it s=
eems
the anonymous union is confusing it.

> If so, could we make the message clearer, adding: "the following designat=
ed
> fields X,Y,Z will be default initialized. P,Q,R are left uninitialized."

How would P,Q,R be left uninitialized?

> That way, it is much more useful as a warning, instead of making the dev
> fear of undefined behavior, when there is not.

It doesn't say anything about undefined behaviour.=