https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91653
TC <rs2740 at gmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |rs2740 at gmail dot com --- Comment #3 from TC <rs2740 at gmail dot com> --- Looks NAD to me. http://eel.is/c++draft/ostream.inserters#8.2 doesn't say that we set any bit in that case. Contrast with http://eel.is/c++draft/ostream.unformatted#3 and http://eel.is/c++draft/ostream.unformatted#5.2