wchartest.c

#include <stdio.h>
#include <wchar.h>

int main(void)
{
    printf("%d\n", sizeof(wchar_t));
    
    return 0;
}

wchartest.d

import std.stdio;

void main()
{
    writeln("wchar = ", wchar.sizeof);
    writeln("dchar = ", dchar.sizeof);
}