wctomb() accepts out-of-range character in C-locale

[Jun. T]

> 2024/03/26 20:48、Steven J Abner <pheonix.sja@att.net>のメール:
> 
> The character codes 0x80-0xFF are not really implementation defined. They are classified
> as 'cntl' codes, thou not officially stated, and valid codes. 

In the current newlib, 0xe1 in C-locale corresponds to
the character U+00e1 = á (printable).

Anyway, newlib can do anything it wants.
But I think you can't expect other systems will do the
same thing.