https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91235
--- Comment #1 from Daniel Fruzynski <bugzi...@poradnik-webmastera.com> --- I checked that trunk gcc also accepts this code, both with -std=c++11 and -std=c++1z. Clang also compiles this without error. Could someone take a look on this and add some comment here?