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From: "fchelnokov at gmail dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/102116] New: structured binding is returned from a function as rvalue in C++20 mode Date: Sun, 29 Aug 2021 09:27:24 +0000 [thread overview] Message-ID: <bug-102116-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102116 Bug ID: 102116 Summary: structured binding is returned from a function as rvalue in C++20 mode Product: gcc Version: 12.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: fchelnokov at gmail dot com Target Milestone: --- In the following program: ``` #include <tuple> #include <iostream> struct A { A(const int &) { std::cout << "A(const int &) "; } A(int &&) { std::cout << "A(int &&) "; } }; A foo() { auto [y] = std::make_tuple(1); return y; } int main() { foo(); } ``` GCC selects "A(int &&)" constructor starting from C++20 mode, demo: https://gcc.godbolt.org/z/5q779vE6T I asked why on stack-overflow: https://stackoverflow.com/questions/68941451/shall-structured-binding-be-returned-from-a-function-as-rvalue-in-c20 and the answer was that GCC being wrong here. Could you please confirm it or explain why the behavior of the program changes in C++20 mode?
next reply other threads:[~2021-08-29 9:27 UTC|newest] Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-08-29 9:27 fchelnokov at gmail dot com [this message] 2021-09-02 6:46 ` [Bug c++/102116] " fchelnokov at gmail dot com 2021-09-02 6:55 ` pinskia at gcc dot gnu.org 2021-09-02 7:04 ` fchelnokov at gmail dot com 2021-09-02 7:13 ` jakub at gcc dot gnu.org
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