结构体中字段类型的改变直接造成内存对齐结果的改变,是的占用内存空间也不一样
package main
import (
"fmt"
"unsafe"
)
func main() {
var xx struct {
a bool
b int32
c []int
}
var x struct {
a int32
b []int
c bool
}
fmt.Println("SIZE")
fmt.Println(unsafe.Sizeof(x)) //32
fmt.Println(unsafe.Sizeof(xx)) //40
fmt.Println(unsafe.Sizeof(x.a))
fmt.Println(unsafe.Sizeof(x.b))
fmt.Println(unsafe.Sizeof(x.c))
fmt.Println("ALIGN")
fmt.Println(unsafe.Alignof(x))
fmt.Println(unsafe.Alignof(x.a))
fmt.Println(unsafe.Alignof(x.b))
fmt.Println(unsafe.Alignof(x.c))
fmt.Println("OFFSET")
fmt.Println(unsafe.Offsetof(x.a))
fmt.Println(unsafe.Offsetof(x.b))
fmt.Println(unsafe.Offsetof(x.c))
}