Is possible the deadlock happened if we don't use channel?-CodePudding

A deadlock happens when a group of goroutines are waiting for each other and none of them is able to proceed.

For example:

func main() {
        ch := make(chan int)
        ch <- 1
        fmt.Println(<-ch)
}

But is there any possibility the deadlock happened if we don't use channel?

CodePudding user response：

In order to have a deadlock, you just need one (or more) components to be waiting in such a way that noone will proceed first.

A channel is a common way to experience a deadlock in Go, but anything that is used for synchronization can trigger it as well.

Here are just some examples of simple deadlocks:

package main

import "sync"

func main() {
    var mu sync.Mutex
    mu.Lock()
    mu.Lock()
}

package main

import "sync"

func main() {
    var wg sync.WaitGroup
    wg.Add(1)
    wg.Wait()
}