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From: "ppalka at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/103924] views::join combined with std::string cannot
 be used in constant expressions
Date: Tue, 04 Oct 2022 14:41:39 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D103924

--- Comment #1 from Patrick Palka <ppalka at gcc dot gnu.org> ---
I encountered a similar problem when testing views::join_with:

#include <string>
#include <ranges>
constexpr std::string_view rs[] =3D {"42"};
static_assert(!std::ranges::empty(rs |
std::views::join_with(std::string(""))));

error: accessing =E2=80=98std::__cxx11::basic_string<char>::<unnamed
union>::_M_allocated_capacity=E2=80=99 member instead of initialized
=E2=80=98std::__cxx11::basic_string<char>::<unnamed union>::_M_local_buf=E2=
=80=99 member in
constant expression=