golang 中内存模型

 

https://segmentfault.com/a/1190000008230146

 

 

 

 

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package main   import (   "time"   "log" )   var a string   func hello() {   time.Sleep(time.Millisecond * 900) // 这里如果sleep 1 秒的话， 执行程序时可能看不到打印的 “hello”   log.Println(a) }   func main() {   a = "hello\n"   go hello()   time.Sleep(time.Second) }

　　

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package main   import ( //  "log"   "time" )   var a string var c = make(chan int) func main() {   go func() {     a = "hello\n"   print("recv begin..\n")   time.Sleep(time.Second*3)   <-c   sum :=0                        //后面这四行注释，打印顺序变为：sb, rb, re,se.  不注释时打印顺序可能为：sb,rb,re,se. (sb: send begin, se: send end..)   for i := 0; i<1<<24; i++ {     sum += i   }   print("recv end..\n")   }()     print("send begin..\n")     c <-12     print("send end..\n")   print(a)   time.Sleep(time.Second*2) }

　　

 

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