MISRA C:2012 Dir 4.11

The validity of values passed to library functions shall be checked

Description

Directive Definition

The validity of values passed to library functions shall be checked¹ .

Rationale

Many Standard C functions do not check the validity of parameters passed to them. Even if checks are performed by a compiler, there is no guarantee that the checks are adequate. For example, you should not pass negative numbers to sqrt or log.

Polyspace Implementation

Polyspace^® reports violation of this directive if any of these issues are detected:

• Invalid use of standard library floating point routine.

• Invalid use of standard library routine.

• Standard function call with incorrect arguments.

• Invalid use of standard library integer routine. Polyspace does not report a violation of this directive on invalid use of some integer library routines such as isalnum, isalpha, or tolower.

• Invalid use of standard library memory routine. Polyspace does not report a violation of this directive on invalid use of some memory library routines such as memchr, memcmp, or memset.

• Invalid use of standard library string routine. Polyspace does not report a violation of this directive on invalid use of some string library routines such as strncat, strncpy, or strcpy.

• Invoking trigonometric functions from math.h using inputs outside the bound [-π,π].

Tip

To mass-justify all results related to the same library function, use the Detail column on the Results List pane. Click the column header so that all results with the same entry are grouped together. Select the first result and then select the last result while holding the Shift key. Assign a status to one of the results. If you do not see the Detail column, right-click any other column header and enable this column.

Troubleshooting

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

Check Information

Group: Code design

Category: Required

AGC Category: Required

Version History

Introduced in R2014b

R2024a: Calling trigonometric functions using values outside the bound [-π,π] is a violation

Calling the periodic trigonometric functions in math.h using large values results in loss of precision and can eventually lead to incorrect outcome. The rule checker reports a violation if the periodic trigonometric functions in math.h are invoked using values outside the range [-π,π].