When %d converts a pointer value, it prints it in hexadecimal.  I would expect %d to
print decimal, but the fmt documentation doesn't specify this case.

(Personally I'd prefer that converting a pointer other than via %v or %p was a runtime
error, or better still, a static error when the format string is literal, as in gcc.)

http://play.golang.org/p/7sPim-5UgD

So:
- please document/specify the intended behaviour.
- please honor the radix of the conversion specifier.