From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
	id 528C13858C20; Tue,  6 Feb 2024 10:41:27 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 528C13858C20
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1707216087;
	bh=+Oaj0tbpYzRSSNv3qmZwOJd6sJ+TxatO8ZoPEMcGeNY=;
	h=From:To:Subject:Date:From;
	b=VzdlV9HO77Vyv7JDYtLKJMTLmmCdPGCmHb/Yl6/MeeWIB8QGZp2YAlDpLBHmArBnL
	 Njmoq4Dcy9j03w9n6/uz8vKSp+Eygwy7SuW8v7YXhY55hMGr0NZ6ylZVvclsPBBVmZ
	 I5jcqL7wEZnydFCtntsp1L4tCNWi2J+83DqjoovU=
From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/113782] New: constexpr on std::initializer_list,
 std::pair and std::tuple is non-conforming for C++11
Date: Tue, 06 Feb 2024 10:41:26 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: new
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: libstdc++
X-Bugzilla-Version: 14.0
X-Bugzilla-Keywords: accepts-invalid
X-Bugzilla-Severity: normal
X-Bugzilla-Who: redi at gcc dot gnu.org
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status
 keywords bug_severity priority component assigned_to reporter
 target_milestone
Message-ID: <bug-113782-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
List-Id: <gcc-bugs.sourceware.org>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D113782

            Bug ID: 113782
           Summary: constexpr on std::initializer_list, std::pair and
                    std::tuple is non-conforming for C++11
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Keywords: accepts-invalid
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: redi at gcc dot gnu.org
  Target Milestone: ---

https://wg21.link/N3471 should be a C++14 change, not present in C++11 mode.

i.e. this should be rejected with -std=3Dc++11

#include <utility>
#include <tuple>
#include <initializer_list>

constexpr std::initializer_list<int> il{1,2,3};
constexpr int i =3D std::move(*il.begin()) + end(il)[-1] + (int)il.size();
constexpr std::pair<int, int> p{1, 2};
constexpr int j =3D std::get<0>(p) + (int)(p =3D=3D p);
constexpr std::tuple<int> t{1};



initializer_list changes:
r0-104226-g900484dee595d9 (this adds FE tests using -std=3Dc++0x)

<utility> function changes:
r0-110341-g9b9e81a0a9cef8 (also touched std::pair)

std::tuple and std::pair changes:
r0-104899-g094a14eff78e4f=