Add a message for if an overflow occurs in core::intrinsics::is_nonoverlapping.

[nullptrderef29]

No description provided.

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[scottmcm]

Since this does something different, can you elaborate on why this is better? Is there a test that should be added?

[nullptrderef29]

I just kind of wanted to get rid of the unwrap, but i can close this if it is better to panic here (maybe add a panic message indicating overflow?), or i could also add some sort of test.

[nullptrderef29]

maybe something like this?

let size = mem::size_of::<T>().checked_mul(count).expect("is_nonoverlapping: size_of::<T>() * count overflows a usize");

[the8472]

is_nonoverlapping is only used in debug asserts, so making the error explicit (overflow is an error here) is fine.

[nullptrderef29]

I have changed it to be an explicit error message on overflow.

[the8472]

@bors r+ rollup

[bors]

📌 Commit 3dba587 has been approved by the8472

It is now in the queue for this repository.