接口切片……如何确保此安全性可同时使用？

I have the following code https://play.golang.org/p/4mlXMhqpLJ:

package main

import (
    "fmt"
)

type A struct {
    Name string
}

func (a *A) method(name string) {
    a.Name = name
}

func (a *A) name() string {
    return a.Name
}

type intt interface {
    method(string)
    name() string
}

var interfacer = []intt{
    &A{},
}

func ExportedMethod(name string) bool {
    for _, aa := range interfacer {
        fmt.Println("Pre:", aa.name())
        aa.method(name)
        fmt.Println("Post:", aa.name())
        if aa.name() == "Fred" {
            return true
        }
    }
    return false
}

func main() {
    ExportedMethod("Bob")
    ExportedMethod("Frank")
}

Since my second for loop prints Bob it is apparent that this is not safe for concurrent use. This is a simple example. In reality, I have many more structs that are going to satisfy interfacer...&B{}, &C{}, &D{}, &E{}, etc...I need a way to be able to loop through all of the structs, which is why I have a slice of interfacer. How can I make this safe for concurrent use?