[LegionMammal978]

Because the 'bug' as presented in the article applies to binary search over an array that has a natural maximum length. If you weren't using an array, there'd be nothing constraining the magnitude of the indices, so you might as well go straight to bigints.

[chowells]

Of course there's a natural constraint: the type of the function. You can't pass a bigint to a function that expects an int. And if you are just blind casting, it turns out you have a similar bug: you are calling the function with different arguments than you think you are. It's the same underlying problem with a different expression in some cases.