https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121745
--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jonathan Wakely <[email protected]>: https://gcc.gnu.org/g:c8a24f60b6874fca4fb3adb153f8d5f1dd72b951 commit r16-3541-gc8a24f60b6874fca4fb3adb153f8d5f1dd72b951 Author: Jonathan Wakely <[email protected]> Date: Mon Sep 1 18:12:27 2025 +0100 libstdc++: Fix std::get<T> for std::pair with reference members [PR121745] Make the std::get<T> overloads for rvalues use std::forward<T>(p.first) not std::move(p.first), so that lvalue reference members are not incorrectly converted to rvalues. It might appear that std::move(p).first would also work, but the language rules say that for std::pair<T&&, U> that would produce T& rather than the expected T&& (see the discussion in P2445R1 §8.2). Additional tests are added to verify all combinations of reference members, value categories, and const-qualification. libstdc++-v3/ChangeLog: PR libstdc++/121745 * include/bits/stl_pair.h (get): Use forward instead of move in std::get<T> overloads for rvalue pairs. * testsuite/20_util/pair/astuple/get_by_type.cc: Check all value categories and cv-qualification. Reviewed-by: Tomasz KamiÅski <[email protected]>
