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From: "martin.ankerl at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/84476] [[nodiscard]] ignored on virtual functions accessed
 through pointer
Date: Wed, 21 Apr 2021 16:48:16 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D84476

Martin Ankerl <martin.ankerl at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |martin.ankerl at gmail dot=
 com

--- Comment #1 from Martin Ankerl <martin.ankerl at gmail dot com> ---
I just "discovered" this bug as well. The warning works correctly in g++ 6.=
4,
but starting from 7.1 upwards it does not work any more.

My reproducer which is very similar:=20

struct Foo {
        [[nodiscard]] virtual bool foo() { return true; };
    virtual ~Foo() =3D default;
};


void shouldEmitWarning() {
    auto* f =3D new Foo();
    f->foo(); // <-- why no warning here?
    delete f;
}

Godbolt link: https://godbolt.org/z/xqaPrshYn=