golang出现panic是什么原因

package main import "fmt" import "runtime/debug" func fun() { fmt.Println("fun begin") defer func() { //捕获panic if err := recover(); err != nil { debug.PrintStack() //获取堆栈信息的字符串 fmt.Println("xxx", string(debug.Stack())) } }() var p *int //产生异常 *p = 0 fmt.Println("fun end") //这里不执行 for {} } func main() { fmt.Println("main begin") fun() //因为panic被recover捕获，所以下面继续执行 fmt.Println("main end") for {} }

main begin fun begin goroutine 1 [running]: runtime/debug.Stack(0xc000088060, 0xc00009a000, 0xa) /usr/local/Cellar/go/1.11.1/libexec/src/runtime/debug/stack.go:24 +0xa7 runtime/debug.PrintStack() /usr/local/Cellar/go/1.11.1/libexec/src/runtime/debug/stack.go:16 +0x22 main.fun.func1() /Users/xxx/test/a.go:10 +0x46 panic(0x10a9760, 0x115d520) /usr/local/Cellar/go/1.11.1/libexec/src/runtime/panic.go:513 +0x1b9 main.fun() /Users/xxx/test/a.go:16 +0x7f main.main() /Users/xxx/test/a.go:24 +0x66 xxx goroutine 1 [running]: runtime/debug.Stack(0xc00007ada8, 0x10a9760, 0x115d520) /usr/local/Cellar/go/1.11.1/libexec/src/runtime/debug/stack.go:24 +0xa7 main.fun.func1() /Users/xxx/test/a.go:11 +0x4b panic(0x10a9760, 0x115d520) /usr/local/Cellar/go/1.11.1/libexec/src/runtime/panic.go:513 +0x1b9 main.fun() /Users/xxx/test/a.go:16 +0x7f main.main() /Users/xxx/test/a.go:24 +0x66 main end