Do you know what version that happens in? I tested on my 32 and 64 bit platforms with golang 1.1 and a static definition of an integer results in type int (which is explicitly 32 bit)

  package main
  import "fmt"
  import "reflect"
  func main() {
      i := 3
      z := reflect.ValueOf(i)
      fmt.Printf("%s\n", z.Kind()) 
  }
  // $./test
  // int
  // $

It's my understanding that this intentional and won't change, only explicit declarations of int64 are 64-bit.