On Tue, Mar 2, 2021 at 3:46 PM Peter Brett via SG16 <sg16@lists.isocpp.org> wrote:
I would like to know if there is consensus that producing mojibake is always a bug.


Given the untyped APIs we are talking about, I'd say that mojibake is a bug due to unenforceable preconditions.
If someone actually desires mojibake, for whatever reason, it's not a bug that the byte oriented string functions allow broken multibyte characters to be created. 

If we were discussing a std::text_view proposal, I might have different positions. But NTBSs and NTMBSs are inherently mojibake enabled, especially since they have the same type.