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From: "Simon.Richter at hogyros dot de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/114675] New: warning for "reference to not fully
 constructed object"
Date: Wed, 10 Apr 2024 09:15:47 +0000
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X-Bugzilla-Product: gcc
X-Bugzilla-Component: c++
X-Bugzilla-Version: 13.1.1
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X-Bugzilla-Who: Simon.Richter at hogyros dot de
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114675

            Bug ID: 114675
           Summary: warning for "reference to not fully constructed
                    object"
           Product: gcc
           Version: 13.1.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: Simon.Richter at hogyros dot de
  Target Milestone: ---

We have an object that contains several sub-objects that should reference e=
ach
other through interface pointers. I'd like to make sure that interface poin=
ters
given to objects constructed later already point to initialized objects.

So, for

struct everything {
    everything() : a(), b(c), c(a) { }

    A a;
    B b;
    C c;
};

I'm passing a reference to the not-yet-constructed C object to B's construc=
tor,
so this is unsafe despite being legal C++. I wonder if it would be possible=
 to
generate a warning here.=