https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98642
--- Comment #1 from Marek Polacek <mpolacek at gcc dot gnu.org> --- $ ./cc1plus -quiet 98642.C 98642.C: In instantiation of ‘C& bar() [with C = const foo]’: 98642.C:19:25: required from here 98642.C:13:12: error: use of deleted function ‘base::base(base&&)’ 13 | static C c{}; | ^ 98642.C:4:3: note: declared here 4 | base(base &&) = delete; | ^~~~