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MISRA C:2023 Rule 17.11

A function that never returns should be declared with a _Noreturn function specifier

Since R2024a

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Description

Rule Definition

A function that never returns should be declared with a _Noreturn function specifier.

Rationale

If you declare a function with the _Noreturn specifier, it becomes explicit that the function is not intended to return. Otherwise, it is unclear if the function that does not return because of an error in the program logic.

Polyspace Implementation

The rule checker analyzes the body of a function and reports a violation if the function cannot return to its caller but is not declared as _Noreturn.

This rule violation is reported only if you specify a C standard version of C11 or later for the Bug Finder analysis. For more information, see C standard version (-c-version).

Troubleshooting

If you expect a rule violation but do not see it, refer to Diagnose Why Coding Standard Violations Do Not Appear as Expected.

Examples

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In this example, both the functions verifyID() and assessID() invoke the _Noreturn function checkID() and therefore cannot return to their callers.

  • The function verifyID() is not declared as _Noreturn, therefore violates the rule.

  • The function assessID() is declared as _Noreturn and does not violate the rule.

#include <stdint.h>

_Noreturn void checkID(int32_t ID);

void verifyID(int32_t ID) { // Noncompliant
    checkID(ID);
}

_Noreturn void assessID(int32_t ID) { // Compliant
    checkID(ID);
}

Check Information

Group: Functions
Category: Advisory
AGC Category: Advisory

Version History

Introduced in R2024a

See Also

Topics