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Unary - still has higher precedence in C (over the bitwise XOR operator).

In case you mean exponentiation, these expressions would always be equal regardless of the precedence of the operators.

(-3)^4 != -(3^4) when ^ means exponentiation.

It does for the expression given, silly. And again, in mathematical notation, unary - would take precedence over exponentiation so it's completely unclear what that person's example is supposed to mean and why it has upvotes.

I was actually originally going to say -3 * 5 = -(3 * 5), as a joke. But from what I could find online, it looks like unary minus traditionally falls below exponentiation in the order of operations for math. See http://mathforum.org/library/drmath/view/53194.html and Wikipedia: "In written or printed mathematics, the expression −3^2 is interpreted to mean −(3^2) = −9."

I think we have a QED here. :)

Obviously there are some cases where you should use parentheses. The reference operator just seems like a strange place to draw the line. I mean, to me it seems like the least confusing part of the quoted line.

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