Because printf format strings are interpreted at runtime, rather than validated by the compiler, they can contain errors that result in the wrong strings being created. This rule statically validates the correlation of printf format strings to their arguments.

The related rule {rule:cpp:S2275} is about errors that will create undefined behavior, while this rule is about errors that produce an unexpected string.

Noncompliant Code Example

printf("%d", 1, 2); // Noncompliant; the second argument "2" is unused
printf("%0-f", 1.2); // Noncompliant; flag "0" is ignored because of "-"

Compliant Solution

printf("%d %d", 1, 2); // Compliant
printf("%-f", 1.2); // Compliant

Exceptions

This rule will only work if the format string is provided as a string literal.

See