废话不说了，直接上代码

package main

import "unsafe"
import "fmt"

func abc() {
	type T struct {
		a int
		b int
		c int
	}

	type SliceHeader struct {
		addr uintptr
		len  int
		cap  int
	}

	t := &T{a: 1,b: 2,c: 3}
	p := unsafe.Sizeof(*t)
	println(int(p))

	sl := &SliceHeader{
		addr: uintptr(unsafe.Pointer(t)),len:  int(p),cap:  int(p),}

	b := *(*[]byte)(unsafe.Pointer(sl))
	println(len(b))
	fmt.Println(b)

	b[0] = 7
	b[4] = 5
	b[8] = 8

	fmt.Println(t)

}

func main() {
	abc()
}