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A comment on Learning that you can use unions in C for grouping things into namespaces. Parent comment

Re:Learning that you can use unions in C for grouping things... by rocqua on Sunday August 01, 2021 @06:40PM (#28030870)
GCC explicitly states znd documents that type punning through unions will work as expected. This doesn't work by accident. It works very explicitly by design of GCC.

Different GCC versions aren't randomly going to change documented behavior. And when they accidentally do, they will consider it a bug.

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Re:Learning that you can use unions in C for grouping things... by comex on Sunday August 01, 2021 @10:54PM (#28032417)
Regardless, type punning though a union is not undefined behavior in C the first place [1] [2]. On the other hand, it is undefined in C++, but GCC allows it there too.

[1] https://stackoverflow.com/questions/11639947/is-type-punning...

[2] https://stackoverflow.com/questions/25664848/unions-and-type...

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