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No Diagnostic Required

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"无需诊断" 表示某些措辞根据语言规则属于病构形式,但编译器无需发出任何诊断信息或错误消息。通常原因是检测这些情况会导致编译时间过长。

若执行此类程序, 其行为是未定义的

参见

C 文档 关于 No Diagnostic Required