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asdfaoeu | 1 year ago

How can it both have no side effects and have undefined behaviour?

discuss

order

masklinn|1 year ago

By being declared as that?

Division has no side effects, and division by 0 is UB. UBs only occur in invalid programs, so behaviour in case of UB is not relevant to a discussion of side effects or their lack thereof, in language terms these are not programs at all.

asdfaoeu|1 year ago

If print statement never completes then it is a well defined program. Because there will be no division by zero.

sapiogram|1 year ago

Both statements don't need to be true. The compiler just has to prove that at least one of the statements will always be true.

asdfaoeu|1 year ago

True but it only has no side effects if it's well defined. The compiler can assume it's well defined but only if it's executed.