# fatal error: 并发写 map

- **ID:** `go/concurrent-map-write`
- **领域:** go
- **类别:** runtime_error
- **验证级别:** ai_generated
- **修复率:** 80%

## 根因

两个 goroutine 在无同步的情况下写同一个 map。运行时检测到并发写 map 会直接终止进程，无法 recover。

## 版本兼容性

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

## 解决方案

1. **** (97% 成功率)
   ```
   var mu sync.RWMutex
mu.Lock()
m[k] = v
mu.Unlock()

mu.RLock()
v := m[k]
mu.RUnlock()
   ```
2. **** (90% 成功率)
   ```
   var m sync.Map
m.Store(k, v)
if v, ok := m.Load(k); ok { _ = v }
   ```

## 无效尝试

- **** — fatal error is not a panic; recover cannot intercept it. The process dies regardless. (99% 失败率)
- **** — If reads also race with writes, the runtime may still report concurrent map read and map write. Both paths need protection. (60% 失败率)