https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100589
Bug ID: 100589 Summary: function with trailing return type must specify return type 'auto' instead of 'concept auto' Product: gcc Version: 11.1.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: stanislaw.w.morawski at gmail dot com Target Milestone: --- https://godbolt.org/z/jnahsxrnq Behaviour: Concept is being ignored when used with auto keyword preceding function with trailing return type. Expected Behaviour: Syntax error: improper use of concept.