Order of evaluation for most of the binary operators is left undefined to give the compiler opportunities for optimization

I think that is an acceptable trade-off. When an expression refers to and change the same object, we can always seperate that expression into several expressions to avoid the situation except where:

  - The operator involved is one of _and `&&`, or `||`, conditional `?:`, comma `,`_ operator,

  - The subexpression that change the operand is itself the operand of another subexpression.