https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116276
--- Comment #4 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Patrick Palka <ppa...@gcc.gnu.org>: https://gcc.gnu.org/g:8cc67b520968ca9a13fd96896522aa66e39a99e2 commit r15-2864-g8cc67b520968ca9a13fd96896522aa66e39a99e2 Author: Patrick Palka <ppa...@redhat.com> Date: Fri Aug 9 21:15:25 2024 -0400 c++: inherited CTAD fixes [PR116276] This implements the overlooked inherited vs non-inherited guide tiebreaker from P2582R1. This requires tracking inherited-ness of a guide, for which it seems natural to reuse the lang_decl_fn::context field which for a constructor tracks its inherited-ness. This patch also works around CLASSTYPE_CONSTRUCTORS not reliably returning all inherited constructors (due to some using-decl handling quirks in in push_class_level_binding) by iterating over TYPE_FIELDS instead. This patch also makes us recognize another written form of inherited constructor, 'using Base<T>::Base::Base' whose USING_DECL_SCOPE is a TYPENAME_TYPE. PR c++/116276 gcc/cp/ChangeLog: * call.cc (joust): Implement P2582R1 inherited vs non-inherited guide tiebreaker. * cp-tree.h (lang_decl_fn::context): Document usage in deduction_guide_p FUNCTION_DECLs. (inherited_guide_p): Declare. * pt.cc (inherited_guide_p): Define. (set_inherited_guide_context): Define. (alias_ctad_tweaks): Use set_inherited_guide_context. (inherited_ctad_tweaks): Recognize some inherited constructors whose scope is a TYPENAME_TYPE. (ctor_deduction_guides_for): For C++23 inherited CTAD, iterate over TYPE_FIELDS instead of CLASSTYPE_CONSTRUCTORS to recognize all inherited constructors. gcc/testsuite/ChangeLog: * g++.dg/cpp23/class-deduction-inherited4.C: Remove an xfail. * g++.dg/cpp23/class-deduction-inherited5.C: New test. * g++.dg/cpp23/class-deduction-inherited6.C: New test. Reviewed-by: Jason Merrill <ja...@redhat.com>
