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From: "mpolacek at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/85043] -Wuseless-cast false positive for temporary objects;
 add separate -Wcast-to-the-same-type to cover that case instead
Date: Tue, 18 Oct 2022 13:48:42 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D85043

--- Comment #14 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
I've encountered this bug with:

struct S { };
void g(S&&);

void
f (S&& arg)
{
  g(S(arg)); // warning: useless cast to type 'struct S'
}

which doesn't compile without the cast, because then "arg" is an lvalue that
cannot bind to S&&.

I'd like to disable then warning when a class is cast to a non-reference ty=
pe.=