15.2.27 Noreturn Function Attribute

The noreturn attribute indicates to the compiler that the function will never return. In some situations, this can allow the compiler to generate more efficient code in the calling function since optimizations can be performed without regard to behavior if the function ever did return. Functions declared as noreturn should always have a return type of void. For example:

void __attribute__ ((noreturn)) myExit(void);