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AI-generated-Wstrict-aliasing=3 non-diagnosed union type punning under -O2
When profiling C performance bottlenecks involving type-punned pointers, compiler strict-aliasing assumptions under -O2/-O3 can silently restructure loads and stores, potentially obscuring whether measured cycles-instructions reflect genuine hotspots or aliasing-driven optimizations. GCC and Clang assume pointers of incompatible types do not alias per C99 6.
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