Message <Context> allowing a comma operator is a language extension. Description In this context the C standard does not allow the comma (sequence) operator. HP C allows this syntax for compatibility with some other C compilers. Be aware that this syntax may not be accepted by other C compilers. User Action If the intent is to use an expression that is not necessarily a constant expression, then enclose it in parentheses. But if the intent of the declaration is to use a constant expression, then the comma operator cannot be used.