# 恐慌：同步：WaitGroup 计数器为负

- **ID:** `go/deadlock-waitgroup-misuse`
- **领域:** go
- **类别:** runtime_error
- **验证级别:** ai_generated
- **修复率:** 80%

## 根因

调用 Done() 的次数多于 Add()，导致计数器变为负数，引发恐慌。

## 版本兼容性

| 版本 | 状态 | 引入 | 弃用 |
|------|------|------|------|
| 1.18 | active | — | — |

## 解决方案

1. **** (95% 成功率)
   ```
   var wg sync.WaitGroup
wg.Add(1)
go func() {
    defer wg.Done()
    // work
}()
wg.Wait()
   ```
2. **** (90% 成功率)
   ```
   // Ensure Add is called before starting goroutines
wg.Add(2)
go func() { defer wg.Done(); /* work */ }()
go func() { defer wg.Done(); /* work */ }()
wg.Wait()
   ```

## 无效尝试

- **** — Recovery doesn't fix the logic error; program state is inconsistent. (70% 失败率)
- **** — Panic crashes the program unless recovered. (100% 失败率)
- **** — Doesn't prevent negative if Done is called too many times. (80% 失败率)