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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++/114410] compiler issue in reference_binding when using
 rvalue reference to member of const object
Date: Thu, 21 Mar 2024 10:25:30 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114410

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> ---
No, because a (T) style cast can do almost anything. In this case it's
equivalent to

const_cast<std::string&>(static_cast<const std::string&>(a->m_i))

which is valid code.

-Wold-style-cast will warn about using any form of (T) cast, which can
encourage you to be more careful and precise about what you're trying to do.

If you had written it like this:

std::cout << static_cast<std::string&>(a->m_i) << std::endl;

Then it wouldn't even compile.

tl;dr don't use C-style casts if you want the compiler to tell you when you=
're
doing something wrong.=