Everything in C is undefined behavior

Article summary

C语言标准中"未定义行为"(UB)的边界远比开发者想象的模糊。本文深入剖析了那些看似无害却触发UB的常见代码模式——从有符号整数溢出到严格别名违规，揭示编译器如何利用UB进行激进优化。理解这些暗礁不仅能避免诡异的生产环境bug，更能帮助开发者写出真正可移植、可预测的高性能C代码，是系统编程人员的必读警示。

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Everything in C is undefined behavior #

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