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MISRA C:2012 Rule Enforcement 

(MISRA C:2012 Third Edition, First Revision plus Amendment 2)

ENFORCEMENT FOR KW 2023.4

 

 

Total

a

Total Number of Rules

175

b

Total Number of ‘Not Statically Enforceable’ Rules (Assisted/Unassisted)

17

c

Total Number of Enforceable Rules (a-b)

158

d

Total Number of Enforced Rules

154

e

Total Number of Unenforced Rules

4

f

Enforce Rules Percentage (d/c)

97%

g

Unenforced Rules Percentage (e/c)

3%

PR indicates rule is covered by an external tool       
 

Rule

Rule Description

Category

Analysis

Enforced

Notes

1.1

The program shall contain no violations of the standard C syntax and constraints, and shall not exceed the implementation's translation limits

Required

Decidable

Yes

Compiler warnings

1.2

Language extensions should not be used

Advisory

Undecidable

Yes

 

1.3

There shall be no occurrence of undefined or critical unspecified behaviour

Required

Undecidable

No

 

1.4

Emergent language features shall not be used.

Required

Decidable

Yes

 

2.1

A project shall not contain unreachable code

Required

Undecidable

Yes

 

2.2

There shall be no dead code

Required

Undecidable

Yes

 

2.3

A project should not contain unused type declarations

Advisory

Decidable

Yes

 

2.4

A project should not contain unused tag declarations

Advisory

Decidable

Yes

 

2.5

A project should not contain unused macro declarations

Advisory

Decidable

Yes

PR

2.6

A function should not contain unused label declarations

Advisory

Decidable

Yes

 

2.7

There should be no unused parameters in functions

Advisory

Decidable

Yes

 

3.1

The character sequences /* and // shall not be used within a comment

Required

Decidable

Yes

 

3.2

Line-splicing shall not be used in // comments

Required

Decidable

Yes

 

4.1

Octal and hexadecimal escape sequences shall be terminated

Required

Decidable

Yes

 

4.2

Trigraphs should not be used

Advisory

Decidable

Yes

 

5.1

External identifiers shall be distinct

Required

Decidable

Yes

PR

5.2

Identifiers, other than external identifiers and macro identifiers, in the same scope and name space shall be distinct

Required

Decidable

Yes

 

5.3

An identifier declared in an inner scope shall not hide an identifier declared in an outer scope

Required

Decidable

Yes

 

5.4

Macro identifiers shall be distinct

Required

Decidable

Yes

 

5.5

Identifiers shall be distinct from macro names

Required

Decidable

Yes

PR

5.6

A typedef name shall be a unique identifier

Required

Decidable

Yes

 

5.7

A tag name shall be a unique identifier

Required

Decidable

Yes

 

5.8

Identifiers that define objects or functions with external linkage shall be unique

Required

Decidable

Yes

 

5.9

Identifiers that define objects or functions with internal linkage should be unique

Advisory

Decidable

Yes

 

6.1

Bit-fields shall only be declared with an appropriate type

Required

Decidable

Yes

 

6.2

Single-bit named bit fields shall not be of a signed type

Required

Decidable

Yes

 

7.1

Octal constants shall not be used

Required

Decidable

Yes

 

7.2

A "u" or "U" suffix shall be applied to all integer constants that are represented in an unsigned type

Required

Decidable

Yes

 

7.3

The lowercase character "l" shall not be used in a literal suffix

Required

Decidable

Yes

 

7.4

A string literal shall not be assigned to an object unless the object's type is "pointer to const-qualified char"

Required

Decidable

Yes

 

8.1

Types shall be explicitly specified

Required

Decidable

Yes

C90 only.

8.2

Function types shall be in prototype form with named parameters

Required

Decidable

Yes

 

8.3

All declarations of an object or function shall use the same names and type qualifiers

Required

Decidable

Yes

 

8.4

A compatible declaration shall be visible when an object or function with external linkage is defined

Required

Decidable

Yes

 

8.5

An external object or function shall be declared once in one and only one file

Required

Decidable

No

 

8.6

An identifier with external linkage shall have exactly one external definition

Required

Decidable

No

 

8.7

Functions and objects should not be defined with external linkage if they are referenced in only one translation unit

Advisory

Decidable

Yes

PR

8.8

The static storage class specifier shall be used in all declarations of objects and functions that have internal linkage

Required

Decidable

Yes

 

8.9

An object should be defined at block scope if its identifier only appears in a single function

Advisory

Decidable

Yes

PR

8.1

An inline function shall be declared with the static storage class

Required

Decidable

Yes

 

8.11

When an array with external linkage is declared, its size should be explicitly specified

Advisory

Decidable

Yes

 

8.12

Within an enumerator list, the value of an implicitly-specified enumeration constant shall be unique

Required

Decidable

Yes

 

8.13

A pointer should point to a const-qualified type whenever possible

Advisory

Undecidable

Yes

 

8.14

The restrict type qualifier shall not be used

Required

Decidable

Yes

 

9.1

The value of an object with automatic storage duration shall not be read before it has been set

Mandatory

Undecidable

Yes

 

9.2

The initializer for an aggregate or union shall be enclosed in braces

Required

Decidable

Yes

 

9.3

Arrays shall not be partially initialized

Required

Decidable

Yes

 

9.4

An element of an object shall not be initialized more than once

Required

Decidable

Yes

 

9.5

Where designated initializers are used to initialize an array object the size of the array shall be specified explicitly

Required

Decidable

Yes

 

10.1

Operands shall not be of an inappropriate essential type.

Required

Decidable

Yes

 

10.2

Expressions of essentially character type shall not be used inappropriately in addition and subtraction operations.

Required

Decidable

Yes

 

10.3

The value of an expression shall not be assigned to an object with a narrower essential type or of a different essential type category.

Required

Decidable

Yes

 

10.4

Both operands of an operator in which the usual arithmetic conversions are performed shall have the same essential type category

Required

Decidable

Yes

 

10.5

The value of an expression should not be cast to an inappropriate essential type

Advisory

Decidable

Yes

 

10.6

The value of a composite expression shall not be assigned to an object with wider essential type.

Required

Decidable

Yes

 

10.7

If a composite expression is used as one operand of an operator in which the usual arithmetic conversions are performed then the other operand shall not have wider essential type.

Required

Decidable

Yes

 

10.8

The value of a composite expression shall not be cast to a different essential type category or a wider essential type.

Required

Decidable

Yes

 

11.1

Conversions shall not be performed between a pointer to a function and any other type

Required

Decidable

Yes

 

11.2

Conversions shall not be performed between a pointer to an incomplete type and any other type

Required

Decidable

Yes

 

11.3

A cast shall not be performed between a pointer to object type and a pointer to a different object type

Required

Decidable

Yes

 

11.4

A conversion should not be performed between a pointer to object and an integer type

Advisory

Decidable

Yes

 

11.5

A conversion should not be performed from pointer to void into pointer to object

Advisory

Decidable

Yes

 

11.6

A cast shall not be performed between pointer to void and an arithmetic type

Required

Decidable

Yes

 

11.7

A cast shall not be performed between pointer to object and a noninteger arithmetic type

Required

Decidable

Yes

 

11.8

A cast shall not remove any const or volatile qualification from the type pointed to by a pointer

Required

Decidable

Yes

 

11.9

The macro NULL shall be the only permitted form of integer null pointer constant

Required

Decidable

Yes

 

12.1

The precedence of operators within expressions should be made explicit

Advisory

Decidable

Yes

 

12.2

The right hand operand of a shift operator shall lie in the range zero to one less than the width in bits of the essential type of the left hand operand.

Required

Undecidable

Yes

 

12.3

The comma operator should not be used

Advisory

Decidable

Yes

 

12.4

Evaluation of constant expressions should not lead to unsigned integer wrap-around

Advisory

Decidable

Yes

 

12.5

The sizeof operator shall not have an operane which is a function parameter declared as ‘array of type’

Mandatory

Decidable

Yes

 

13.1

Initializer lists shall not contain persistent side-effects

Required

Undecidable

Yes

 

13.2

The value of an expression and its persistent side-effects shall be the same under all permitted evaluation orders

Required

Undecidable

Yes

 

13.3

A Yes expression containing an increment (++) or decrement (--) operator should have no other potential side effects other than that caused by the increment or decrement operator

Advisory

Decidable

Yes

 

13.4

The result of an assignment operator should not be used

Advisory

Decidable

Yes

 

13.5

The right hand operand of a logical && or || operator shall not contain persistent side effects

Required

Undecidable

Yes

 

13.6

The operand of the sizeof operator shall not contain any expression which has potential side-effects

Mandatory

Decidable

Yes

 

14.1

A loop counter shall not have essentially floating type

Required

Undecidable

Yes

 

14.2

A for loop shall be well-formed

Required

Undecidable

Yes

 

14.3

Controlling expressions shall not be invariant

Required

Undecidable

Yes

 

14.4

The controlling expression of an if-statement and the controlling expression of an iteration-statement shall have essentially Boolean type

Required

Decidable

Yes

 

15.1

The goto statement should not be used

Advisory

Decidable

Yes

 

15.2

The goto statement shall jump to a label declared later in the same function.

Required

Decidable

Yes

 

15.3

Any label referenced by a goto statement shall be declared in the same block, or in any block enclosing the goto statement.

Required

Decidable

Yes

 

15.4

There should be no more than one break or goto statement used to terminate any iteration statement.

Advisory

Decidable

Yes

 

15.5

A function should have a single point of exit at the end

Advisory

Decidable

Yes

 

15.6

The body of an iteration-statement or a selection-statement shall be a compound-statement

Required

Decidable

Yes

 

15.7

All if … else if constructs shall be terminated with an else statement

Required

Decidable

Yes

 

16.1

All switch statements shall be well-formed

Required

Decidable

Yes

 

16.2

A switch label shall only be used when the most closely-enclosing compound statement is the body of a switch statement

Required

Decidable

Yes

 

16.3

An unconditional break statement shall terminate every switch clause

Required

Decidable

Yes

 

16.4

Every switch statement shall have a default label

Required

Decidable

Yes

 

16.5

A default label shall appear as either the first or the last switch label of a switch statement.

Required

Decidable

Yes

 

16.6

A default label shall appear as either the first or the last switch label of a switch statement.

Required

Decidable

Yes

 

16.7

A switch-expression shall not have essentially Boolean type

Required

Decidable

Yes

 

17.1

The features of  shall not be used.

Required

Decidable

Yes

 

17.2

Functions shall not call themselves, either directly or indirectly

Required

Undecidable

Yes

 

17.3

A function shall not be declared implicitly

Mandatory

Decidable

Yes

C90 only.

17.4

All exit paths from a function with non-void return type shall have an explicit return statement with an expression

Mandatory

Decidable

Yes

 

17.5

The function argument corresponding to a parameter declared to have an array type shall have an appropriate number of elements.

Advisory

Undecidable

Yes

 

17.6

The declaration of an array parameter shall not contain the static keyword between the [ ]

Mandatory

Decidable

Yes

 

17.7

The value returned by a function having non-void return type shall be used

Required

Decidable

Yes

 

17.8

A function parameter should not be modified

Advisory

Undecidable

Yes

 

18.1

A pointer resulting from arithmetic on a pointer operand shall address an element of the same array as that pointer operand

Required

Undecidable

Yes

 

18.2

Subtraction between pointers shall only be applied to pointers that address elements of the same array

Required

Undecidable

Yes

 

18.3

The relational operators >, >=, < and <= shall not be applied to objects of pointer type except where they point into the same object

Required

Undecidable

Yes

 

18.4

The +, -, += and -= operators should not be applied to an expression of pointer type.

Advisory

Decidable

Yes

 

18.5

Declarations should contain no more than two levels of pointer nesting

Advisory

Decidable

Yes

 

18.6

The address of an object with automatic storage shall not be copied to another object that persists after the first object has ceased to exist

Required

Undecidable

Yes

 

18.7

Flexible array members shall not be declared

Required

Decidable

Yes

 

18.8

Variable-length array types shall not be used

Required

Decidable

Yes

 

19.1

An object shall not be assigned or copied to an overlapping object

Mandatory

Undecidable

Yes

 

19.2

The union keyword should not be used

Advisory

Decidable

Yes

 

20.1

#include directives should only be preceded by preprocessor directives or comments

Advisory

Decidable

Yes

 

20.2

The ', " or \ characters and the /* or // character sequences shall not occur in a header file name

Required

Decidable

Yes

 

20.3

The #include directive shall be followed by either a  or "filename" sequence

Required

Decidable

Yes

 

20.4

A macro shall not be defined with the same name as a keyword.

Required

Decidable

Yes

 

20.5

#undef should not be used

Advisory

Decidable

Yes

 

20.6

Tokens that look like a preprocessing directive shall not occur within a macro argument

Required

Decidable

Yes

 

20.7

Expressions resulting from the expansion of macro parameters shall be enclosed in parentheses.

Required

Decidable

No

 

20.8

The controlling expression of a #if or #elif preprocessing directive shall evaluate to 0 or 1.

Required

Decidable

Yes

 

20.9

All identifiers used in the controlling expression of #if or #elif preprocessing directives shall be #define'd before evaluation.

Required

Decidable

Yes

 

20.1

The # and ## preprocessor operators should not be used

Advisory

Decidable

Yes

 

20.11

A macro parameter immediately following a # operator shall not immediately be followed by a ## operator

Required

Decidable

Yes

 

20.12

A macro parameter used as an operand to the # or ## operators, which is itself subject to further macro replacement, shall only be used as an operand to these operators.

Required

Decidable

Yes

 

20.13

A line whose first token is # shall be a valid preprocessing directive.

Required

Decidable

Yes

 

20.14

All #else, #elif and #endif preprocessor directives shall reside in the same file as the #if, #ifdef or #ifndef directive to which they are related

Required

Decidable

Yes

 

21.1

#define and #undef shall not be used on a reserved identifier or reserved macro name

Required

Decidable

Yes

 

21.2

A reserved identifier or macro name shall not be declared

Required

Decidable

Yes

 

21.3

The memory allocation and deallocation functions of  shall not be used

Required

Decidable

Yes

 

21.4

The standard header file  shall not be used

Required

Decidable

Yes

 

21.5

The standard header file  shall not be used

Required

Decidable

Yes

 

21.6

The Standard Library input/output functions shall not be used

Required

Decidable

Yes

 

21.7

The atof, atoi, atol and atoll functions of  shall not be used

Required

Decidable

Yes

 

21.8

The Standard Library termination functions of  shall not be used.

Required

Decidable

Yes

 

21.9

The library functions bsearch and qsort of  shall not be used

Required

Decidable

Yes

 

21.1

The Standard Library time and date functions shall not be used

Required

Decidable

Yes

 

21.11

The standard header file  shall not be used

Required

Decidable

Yes

 

21.12

The exception handling features of  should not be used

Advisory

Decidable

Yes

 

21.13

Any value passed to a function in  shall be representable as an unsigned char or be the value EOF

Mandatory

Undecidable

Yes

 

21.14

The Standard Library function memcmp shall not be used to compare null terminated strings

Required

Undecidable

Yes

 

21.15

The pointer arguments to the Standard Library functions memcpy, memmove and memcmp shall be pointers to qualified or unqualified versions of compatible types

Required

Decidable

Yes

 

21.16

The pointer arguments to the Standard Library function memcp shall point to either a pointer type, an essentially signed type, an essentially unsigned type, an essentially Boolean type or an essentially enum type

Required

Decidable

Yes

 

21.17

Use of the string handling functions from  shall not result in accesses beyond the bounds of the objects referenced by their pointer parameters

Mandatory

Undecidable

Yes

 

21.18

The size_t argument passed to any function in  shall have an appropriate value

Mandatory

Undecidable

Yes

 

21.19

The pointers returned by the Standard Library functions localeconv, getenv, setlocale or strerror shall only be used as if they have pointer to const-qualified type

Mandatory

Undecidable

Yes

 

21.2

The pointer returned by the Standard Library functions asctime, ctime, gmtime, localtime, localeconv, getenv, setlocale, or strerror shall not be used following a subsequent call to the same function.

Mandatory

Undecidable

Yes

 

21.21

The Standard Library function system of  shall not be used.

Required

Decidable

Yes

 

22.1

All resources obtained dynamically by means of Standard Library functions shall be explicitly released

Required

Undecidable

Yes

 

22.2

A block of memory shall only be freed if it was allocated by means of a Standard Library function.

Mandatory

Undecidable

Yes

 

22.3

The same file shall not be open for read and write access at the same time on different streams.

Required

Undecidable

Yes

 

22.4

There shall be no attempt to write to a stream which has been opened as read-only.

Mandatory

Undecidable

Yes

 

22.5

A pointer to a FILE object shall not be dereferenced.

Mandatory

Undecidable

Yes

 

22.6

The value of a pointer to a FILE shall not be used after the associated stream has been closed.

Mandatory

Undecidable

Yes

 

22.7

The macro EOF shall only be compared with the unmodified return value from any Standard Library function capable of returning EOF

Required

Undecidable

Yes

 

22.8

The value of errno shall be set to zero prior to a call to an errno-setting-function

Required

Undecidable

Yes

 

22.9

The value of errno shall be tested against zero after calling an errno-setting-function

Required

Undecidable

Yes

 

22.1

The value of errno shall only be tested when the last function to be called was an errnosetting- function

Required

Undecidable

Yes

 

 

MISRA C:2012 Directive Enforcement

‘A directive is a guideline for which it is not possible to provide the Yes description necessary to perform a check for compliance.’ MISRA C:2012 Section 6.1. Due to the nature of directives, they are, in theory, not statically enforceable, however, the use of the tools can supply some assistance in checking.

Directives

Rule Description

Category

Assisted

Notes

1.1

Any implementation-defined behaviour on which the output of the program depends shall be documented and understood

Required

Assisted

 

2.1

All source files shall compile without any compilation errors

Required

Assisted

All source files shall compile without any compilation errors - This can only be checked by the actual compiler being used and then we simply import any compilation errors into Klocwork reporting

3.1

All code shall be traceable to documented requirements

Required

Unassisted

Documentation

4.1

Run-time failures shall be minimized

Required

Assisted

 

4.2

All usage of assembly language should be documented

Advisory

Assisted

 

4.3

Assembly language shall be encapsulated and isolated

Required

Assisted

 

4.4

Sections of code should not be "commented out"

Advisory

Unassisted

 

4.5

Identifiers in the same name space with overlapping visibility should be typographically unambiguous

Advisory

Unassisted

 

4.6

typedefs that indicate size and signedness should be used in place of the basic numerical types

Advisory

Assisted

 

4.7

If a function returns error information, then that error information shall be tested

Required

Assisted

 

4.8

If a pointer to a structure or union is never dereferenced within a translation unit, then the implementation of the object should be hidden

Advisory

Unassisted

 

4.9

A function should be used in preference to a function-like macro where they are interchangeable

Advisory

Assisted

 

4.10

Precautions shall be taken in order to prevent the contents of a header file being included more then once

Required

Assisted

 

4.11

The validity of values passed to library functions shall be checked

Required

Unassisted

 

4.12

Dynamic memory allocation shall not be used

Required

Unassisted

 

4.13

Functions which are designed to provide operations on a resource should be called in an appropriate sequence

Advisory

Unassisted

 

4.14

The validity of values received from external sources shall be checked

Required

Assisted