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From: "fchelnokov at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/104282] Copy elision when initializing a base-class
 subobject with aggregate initialization
Date: Fri, 22 Mar 2024 07:52:39 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D104282

--- Comment #8 from Fedor Chelnokov <fchelnokov at gmail dot com> ---
One more inconsistency here:

struct A {
  A() {}=20
  A(A&&) =3D delete;
};

struct B : A { };

int main() {
    // ok in GCC
    B{ A{} };

    // error in GCC
    B b{ A{} };
}

GCC allows temporary creation B{ A{} }, but prohibits variable creation B b{
A{} }. Online demo: https://gcc.godbolt.org/z/YGjYYqo6M

It looks like both must be prohibited as in Clang (or both allowed as in MS=
VC).

Related discussion: https://stackoverflow.com/q/70898525/7325599=