is there a way to determine which way compiler executes an multi condition if statement, at compile time

Question

I want to execute a multi condition if statement like below.

Head* head;
If ((head->next!=NULL)&&(head->next->next!=NULL))

The order of execution is important for the above statement to work without seg fault.

Is there a way to determine with way a compiler executes it, at compile time.

Answer 1

The standard.

You're guaranteed the first expression will be evaluated first.

Furthermore, you're guaranteed that if the first evaluates to false, the second won't be evaluated (look up short-circuiting). If this doesn't happen, the compiler isn't compliant.

Answer 2

The order is always left to right. Thus

(cond1) && (cond2)

will always end up test cond1 first, and, if that's true, cond2.

Answer 3

The && and || operators force left-to-right evaluation and introduce a sequence point, so you are guaranteed that the LHS will be fully evaluated and all side effects applied before the RHS is evaluated.