https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101124
--- Comment #2 from CVS 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:302343d8dd30e34516f74a61ec758d80a6c4d1db commit r12-6691-g302343d8dd30e34516f74a61ec758d80a6c4d1db Author: Jonathan Wakely <jwak...@redhat.com> Date: Tue Jan 18 15:10:06 2022 +0000 libstdc++: Fix ambiguous std::pair constructors [PR101124] The deprecated non-standard std::pair constructors that allow constructing std::pair<move-only-type, pointer-type> from an rvalue and a literal zero where not sufficiently constrained. They were viable when constructing std::pair<copyable-type, pointer-type>, and that case should work fine using the standard constructors. Replace the constraints on the non-standard constructors so they are only viable in cases that should actually be ill-formed according to the standard. Also rename __null_ptr_constant to __zero_as_null_pointer_constant so it matches the name of the -Wzero-as-null-pointer-constant warning. Also make the text of the deprecated warning describe the problem in more detail. libstdc++-v3/ChangeLog: PR libstdc++/101124 * include/bits/stl_pair.h (pair): Adjust constraints on deprecated constructors accepting literal zero as null pointer constant. Improve wording of deprecated attribute. * testsuite/20_util/pair/cons/99957.cc: Check that deprecated constructors do not cause ambiguities for copyable types.
