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The following are the sequence points defined by C99:
- the The call to a function, after the arguments have been evaluated
- the The end of the first operand of the following operators: logical AND &&; logical OR ||; conditional ?; comma ,*
- the The end of a full declarator: declarators;
- the The end of a full expression: an initializer; the expression in an expression statement; the controlling expression of a selection statement (if or switch); the controlling expression of a while or do statement; each of the expressions of a for statement; the expression in a return statement
- immediately Immediately before a library function returns (7.1.4)
- after After the actions associated with each formatted input/output function conversion specifier
- immediately Immediately before and immediately after each call to a comparison function, and also between any call to a comparison function and any movement of the objects passed as arguments to that call
* Note that not all instances of a comma in C code denote a usage of the comma operator. E.g., the comma in passing arguments is NOT the comma operator.
Between the previous and next sequence point an object can only have its stored value modified once by the evaluation of an expression. Additionally, the prior value can be read only to determine the value to be stored.
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