wchar_t designates a wide character type. It is treated as an unsigned short by using the rules for an unsigned short, as specified in [C706] section 14.2.5.

A string attribute can be applied to a pointer or array of type wchar_t. This indicates a string of wide characters, as specified in [C706] section 14.3.4. The terminator for a wide character string is two octets of zero (0).