# <stdnoreturn.h>

**[<stdnoreturn.h>](https://en.cppreference.com/w/c/header/stdnoreturn)** provides the `noreturn` macro (C11), which tells the compiler a function never returns—useful for `die()` or `fatal()` functions that always exit. This suppresses false warnings about missing returns and enables better dead-code elimination.

In C23, `[[noreturn]]` became the attribute syntax; the macro is the C11/C17 spelling.

## Example

This example shows how `noreturn` suppresses the "control reaches end" warning.

```c
// compile: gcc -Wall -o stdnoreturnexample stdnoreturnexample.c
// run: ./stdnoreturnexample
// description: noreturn suppresses control-flow warning

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

noreturn void fail(const char* msg) {
    fprintf(stderr, "error: %s\n", msg);
    exit(1);
}

int safe_div(int a, int b) {
    if (b == 0) fail("divide by zero");
    return a / b;
}

int main() {
    printf("%d\n", safe_div(10, 2));
    return 0;
}
```