25 <stdnoreturn.h> Macros for Non-Returning Functions

This header provides a macro noreturn that is a handy alias for _Noreturn.

Use this macro to indicate to the compiler that a function will never return to the caller. It’s undefined behavior if the so-marked function does return.

Here’s a usage example:

#include <stdio.h>
#include <stdlib.h>
#include <stdnoreturn.h>

noreturn void foo(void) // This function should never return!
{
    printf("Happy days\n");

    exit(1);            // And it doesn't return--it exits here!
}

int main(void)
{
    foo();
}

That’s all there is to it.