https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113841
--- Comment #16 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jonathan Wakely <r...@gcc.gnu.org>: https://gcc.gnu.org/g:8b8e5ed6cd0f3cfe7cdf93200e47c069fd101984 commit r15-2651-g8b8e5ed6cd0f3cfe7cdf93200e47c069fd101984 Author: Jonathan Wakely <jwak...@redhat.com> Date: Thu Mar 7 16:00:01 2024 +0000 libstdc++: Constrain std::basic_string default constructor [PR113841] This is needed to avoid errors outside the immediate context when evaluating is_default_constructible_v<basic_string<C, T, A>> when A is not default constructible. This change is not sufficient to solve the problem because there are a large number of member functions which have a default argument that constructs an allocator. libstdc++-v3/ChangeLog: PR libstdc++/113841 * include/bits/basic_string.h (basic_string::basic_string()): Constrain so that it's only present if the allocator is default constructible. * include/bits/cow_string.h (basic_string::basic_string()): Likewise. * testsuite/21_strings/basic_string/cons/113841.cc: New test.
