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From: "glisse at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/67795] Wrong code generated for conditional expression with cast
Date: Thu, 01 Oct 2015 12:57:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67795

Marc Glisse <glisse at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |UNCONFIRMED
            Version|5.2.0                       |unknown
         Resolution|INVALID                     |---

--- Comment #7 from Marc Glisse <glisse at gcc dot gnu.org> ---
Hmm, with the static_cast, the front-end produces:

<<cleanup_point return <retval> = (struct string_view &) (struct string_view *)
NON_LVALUE_EXPR <(struct string_view &) &(n != 0 ?
std::experimental::fundamentals_v1::basic_string_view<char>::remove_prefix
((struct string_view *) s, n);, *s; : *s)>>>;

while without it, I get:

<<cleanup_point return <retval> = (struct string_view &) (n != 0 ?
std::experimental::fundamentals_v1::basic_string_view<char>::remove_prefix
((struct string_view *) s, n);, (struct string_view *) s; : (struct string_view
*) s)>>;

I also find it fishy.

(note that you need -O2 or more for the warning)