[Bug libstdc++/110339] Implement C++26 library features

[tkaminsk at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110339
Bug 110339 depends on bug 119152, which changed state.

Bug 119152 Summary: [C++26] P3019R14 indirect and polymorphic: Vocabulary Types 
for Composite Class Design
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119152

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED