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Message: [QUOTE="James Kuyper, post: 4215081"] I assume that, if you're willing to have the entire condition evaluated, then neither b nor c represent expressions with side-effects. In particular, neither of them is or involves the value of an object defined with volatile. Then there's two basic cases that need to be distinguished: 1. The compiler can figure out that neither b nor c are expressions with side effects. If this is the case, then any sufficiently good compiler targeting your platform should generate code that evaluates both b and c, and then discarding their values if not needed; at least, it should do so whenever it makes sense to do so. This is allowed by the C standard, even though it says explicitly that they should only be evaluated if needed. That's because of the fact that they have no side-effects. As a result, there's no way for a strictly conforming program to determine whether or not the compiler is doing this, so the as-if rule allows the compiler to do this. If your compiler isn't smart enough to perform this optimization automatically, there's no way in C to tell it explicitly to perform it. 2. The compiler cannot figure out that neither b nor c have side-effects. About the only way this could be true is if one or both of those expressions involve a function call. If all three expressions have integral type, try: if(a & b & c) { } The use of '&' rather than '&&' removes the short-circuiting behavior, but the net result is the same, as long as integer types are involved. If any of the expressions has a floating point or pointer type, you'll have to insert !=0, and that will probably be converted into a branch, which is precisely what you're trying to avoid. [/QUOTE]

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