http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50714
--- Comment #11 from Paolo Carlini <paolo.carlini at oracle dot com> 2011-10-14 09:44:05 UTC --- Note that a codecvt constructor taking (__c_local, size_t) isn't Standard, we don't want it in the primary. If you ask me, not having written this code, I think the cleanest thing to do is simply not defining anything for the primary codecvt_byname and then add two specializations (4 in C++11) quite similar to what we have now in the primary, possibly cleaned-up a bit per your second point. That also solves the apparent "C" locale weirdness, etc (for "C" everything is statically constructed, no work is necessary). This is enhancement work, of course, nobody touched (neither reported bugs for ;) this code for years, and years. All in all, I would recommend doing this as part of C++11 work within a new ABI (then for better compile-time diagnostics we'll also have the option of using deleted special members unconditionally, etc)
