https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109947
Martin Seemann <aemseemann at gmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Resolution|--- |INVALID --- Comment #5 from Martin Seemann <aemseemann at gmail dot com> --- Thanks for the clarification! Now I am convinced that it is not a bug in libstdc++ (although I still doubt that the side-effects were intended when the committee formulated the "Effects" for monadic operations, but that's not relevant here). Marking as resolved and sorry for the noise.