[Bug libstdc++/86419] codecvt::in() and out() incorrectly return partial in some cases.

[dmjpp at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86419

--- Comment #1 from Dimitrij Mijoski <dmjpp at hotmail dot com> ---
Created attachment 44359
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44359&action=edit
test cases that trigger the bug