Static array size limit

[simendsjo]

http://digitalmars.com/d/2.0/arrays.html says static arrays are
limited to 16mb, but I can only allocate 1mb.
My fault, or bug?

        enum size = (16 * 1024 * 1024) / int.sizeof;
        //int[size] a;   // Error: index 4194304 overflow for static
array
        enum size2 = (16 * 1000 * 1000) / int.sizeof;
        //int[size2] b; // Stack Overflow
        //int[250_001] c; // Stack Overflow
        int[250_000] d; // ok