Post operator evaluation order

Question

My friend and I came upon an interesting joke C > C++ since he likes C over C++. However, I am curious as to the validity of executing that code segment. I ran and compiled

int C;
C = 1;std::cout << (C++ < C) << "\n";
C = 1;std::cout << (C < C++) << "\n";
C = 1;std::cout << (C++ > C) << "\n";
C = 1;std::cout << (C > C++) << "\n";

the output was 1 0 0 1 using C++98/C++11, and true, false, false, false for Java.

My question is how does the process of evaluation of these statement work? I get especially confused because C++ < C and C > C++ contradict each other in Java, while staying consistent in C++, as well as the logic of C++ < C, where supposedly the left and right sides are equal or the left side is greater than the right.

The C++ half of this question is a duplicate; some other languages define it. — o11c, Oct 09 '14 at 04:41
Also https://stackoverflow.com/questions/949433/why-are-these-constructs-undefined-behavior — Boann, Oct 09 '14 at 04:43

score 2 · Answer 1 · edited May 23 '17 at 12:05

2

The result is undefined for C/C++ by the specification because the order of evaluation is not specified. See this answer for details.

edited May 23 '17 at 12:05

Community

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answered Oct 09 '14 at 04:39

Dwayne Towell

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http://stackoverflow.com/questions/4176328/undefined-behavior-and-sequence-points – o11c Oct 09 '14 at 04:40

Post operator evaluation order

1 Answers1