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by josephg 1050 days ago
Integer overflows cause panics in debug mode. And its undefined behaviour in release mode.

Where do you see that in the code? I can't see (left+right)/2 anywhere in the code I linked?
2 comments
cornstalks 1050 days ago
> And its undefined behaviour in release mode.

No, it uses 2’s complement and is well defined in release mode. From [1]:

> When you’re compiling in release mode with the --release flag, Rust does not include checks for integer overflow that cause panics. Instead, if overflow occurs, Rust performs two’s complement wrapping.

[1]: https://doc.rust-lang.org/book/ch03-02-data-types.html#integ...

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marcianx 1050 days ago
I'm pretty sure it's not undefined behavior in rust in release mode if it does overflow. It's fully specified behavior, I believe.
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