https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81099
Bug ID: 81099 Summary: A single `decltype(this)` at top level triggers 2 identical error messages Product: gcc Version: 7.1.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: iamsupermouse at mail dot ru Target Milestone: --- If `decltype(this)` is used at top level, it triggers *two* identical error messages. For example: using T = decltype(this); Results in: <source>:1:20: error: invalid use of 'this' at top level using T = decltype(this); ^~~~ <source>:1:20: error: invalid use of 'this' at top level On the other hand, following: auto x = this; // al well as `using T = decltype(*this);` triggers a *single* error message: <source>:1:10: error: invalid use of 'this' at top level auto x = this; ^~~~