alloc_large_mem.go

package main

import (
	"reflect"
	"unsafe"
)

type TestStruct struct {
	A int
	B string
}

var (
	slice []byte
	typ   reflect.Type
)

func init() {
	slice = make([]byte, 1000)
	typ = reflect.TypeOf(TestStruct{})
}

func main() {
	p := (*reflect.SliceHeader)(unsafe.Pointer(&slice))

	buf := p.Data

	value := reflect.NewAt(typ, unsafe.Pointer(buf))

	// 赋值
	test := value.Interface().(*TestStruct)
	test.A = 1234
	test.B = "aaa"

	// 验证是否写入到 buf 内存
	testBuf := (*TestStruct)(unsafe.Pointer(buf))

	println(test.A, test.B)
	println(testBuf.A, testBuf.B)
}