Synopsis

Use valid format strings.

Enabled by default

Yes

Severity/Certainty

High/Low

Full description

The formatted output functions (fprintf() and related functions) convert, format, and print their arguments under control of a format string. The C standard outlines what format specifiers are valid in a format string. This check will find cases where a format string specifier is of an invalid form.

Coding standards

Code examples

The following code example fails the check and will give a warning:

#include <stdio.h>

void example(int i) {
  // Invalid length and type specifier
  printf("%Ld", i);
}

The following code example passes the check and will not give a warning about this issue:

#include <stdio.h>

void example(int i) {
  printf("%hd", i);
}