uint[3] not equivalent to void[12]?

[Ralph Doncaster]

This seems odd to me.  Is there a way I can make a function that 
takes an array of any type but only of a specific size in bytes?

void.d(8): Error: function void.foo (void[12] arr) is not 
callable using argument types (uint[3])
Failed: ["/usr/bin/dmd", "-v", "-o-", "void.d", "-I."]
void foo(void [12] arr)
{
}

void main()
{
     uint[3] arr;
     foo(arr);
}