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CerryuDu • yesterday at 6:23 PM • 1 reply • view on HN

Not to mention the potential signed integer overflow in (*right - *left) and (*left - *right), which is undefined behavior. And even if you rely on common two's complement wraparound, the result may be wrong; for example, (INT_MAX-(-1)) should mathematically yield a positive value, but the function will produce INT_MIN, which is negative.

And then we have this "modern" way of spelling pointers, "const int* right" (note the space). In C, declaration syntax mirrors use, so it should be "const int *right", because "*right" is a "const int".

I feel too old for this shit. :(

Replies

Joker_vD • yesterday at 9:14 PM

    const int left = *(const int*)untyped_left, right = *(const int*)untyped_right;

    return in_reverse?
        (right > left) - (right < left)
      : (left > right) - (left < right);
I wonder if there is a way to actually do it with only arithmetic, without comparisons?