C++ :: Order Of Expression Evaluation In If Statement

This feels to me like a relatively "deep" C syntax question. Reviewing K&R reveals some interesting, related specifications, but I could not nail this down. The issue is, What determines the order in which expressions are evaluated in an if() statement? Now, K&R gives details with regard to the precedence of operator evaluation, but otherwise I could find only 2 sections detailing the order of expression evaluation (I mention these below). A simple code example demonstrates why this is a burning question to me:

Code:
int checkit(int* pi, BOOL bHavePosValue) {
if ((NULL != pi) && *pi > 0) {
bHavePosValue = TRUE;
return (*pi);}
bHavePosValue = FALSE;
return (0);}

So what if pi is passed in NULL? Is it possible for the *pi expression to be evaluated Before the (NULL != pi) expression? If so, you could have an access fault. If not, what rule of C ensures left-to-right evaluation? Is this a simple case of the left-to-right associativity that K&R shows on page 49 (in the table of operator precedence) for the && operator? Or is there some more general rule that applies?

The two mentions in K&R I did find are that function argument evaluation order is Not defined (pg 86). Also, beyond the order specified in the reference section for operators, they state there is no other defined order. In particular, they state:

"Expressions involving a commutative and associative operator (*, +, &, |, ^) may be rearranged arbitrarily, even in the presence of parentheses; "

That surprised me! I suppose the point is that compiler-made changes in this case cannot change the result. I wonder whether this or other similar rules in C were superseded in C++ ?

In a similar vein, what about the expression evaluation order for the for(,,) statement - does it have guaranteed left-to-right order?