Fix

"all goroutines are asleep - deadlock!" in Go

Concurrency
2026-04-17T12:05:42+00:00
Fix the Go deadlock error by ensuring all goroutines are started with 'go' and channel operations have matching senders and receivers.

The "all goroutines are asleep - deadlock!" error occurs when your program has no runnable goroutines, usually because a channel send or receive is blocked waiting for a partner that never arrives. Check for missing go keywords on goroutines, unbuffered channels where one side is blocked, or logic that prevents a goroutine from ever starting.

// Example: Missing 'go' keyword causes deadlock
func main() {
    ch := make(chan int)
    // Missing 'go' here blocks main immediately
    producer(ch) 
    fmt.Println(<-ch) 
}

func producer(ch chan int) {
    ch <- 42 
}

// Fix: Add 'go' to run producer concurrently
func main() {
    ch := make(chan int)
    go producer(ch) // Now runs in background
    fmt.Println(<-ch) 
}

func producer(ch chan int) {
    ch <- 42 
}