# 致命错误：所有协程都处于睡眠状态 - 死锁！（在nil通道上select）

- **ID:** `go/goroutine-select-on-nil-channels`
- **领域:** go
- **类别:** runtime_error
- **验证级别:** ai_generated
- **修复率:** 80%

## 根因

所有通道都为nil的select语句永远阻塞，因为nil通道永远不会就绪。

## 版本兼容性

| 版本 | 状态 | 引入 | 弃用 |
|------|------|------|------|
| 1.0 | active | — | — |
| 1.22 | active | — | — |

## 解决方案

1. **Always include a default case or non-nil channel in select** (95% 成功率)
   ```
   select {
case <-ch1:
case <-ch2:
default:
    // avoid deadlock
}
   ```
2. **Ensure at least one channel is non-nil before select** (90% 成功率)
   ```
   if ch1 == nil && ch2 == nil {
    return // or handle
}
select {
case <-ch1:
case <-ch2:
}
   ```

## 无效尝试

- **Adding a default case that does nothing** — Default case executes immediately, but if omitted, all-nil select blocks. (70% 失败率)
- **Using time.After in select** — time.After returns a non-nil channel, so select won't have all nil channels. (40% 失败率)