https://gcc.gnu.org/bugzilla/show_bug.cgi?id=27775
--- Comment #5 from Rich Newman <rnewman at compubrite dot com> --- (In reply to Manuel López-Ibáñez from comment #4) > Clang 3.0 also reject this, so I am not sure whether is actually valid, but > the repeated messages are suspicious. > EDG accepts it, and I can see nothing wrong with the code according to the standards. The following versions of GCC also reject it with substantially similar error messages: 10.1.0 11.1.0 5.4.0 6.3.0 7.1.0 7.4.0 8.1.0 8.3.0 9.1.0 9.2.0