MISRA C 2012 Checklist

MISRA, the Motor Industry Software Reliability Association, provides world-leading best practice guidelines for the safe application of both embedded control systems and standalone software. The association is a collaboration between manufacturers, component suppliers and engineering consultancies which seeks to promote best practices in developing safety-related embedded electronic systems and other software-intensive applications.

The MISRA C 2012 checklist provides guided checklist review of the directives and rules in the current version of the standard (MISRA C:2012). This review is complete, and is fully automated with the following exceptions. The ⚯ symbol indicates rules that have no automated steps but ask users to attach documentation. Compliance with rules identified by the ☑ symbol is not fully decidable so the corresponding checks include a user review step to eliminate potential false positives.

Software being reviewed with this checklist should be loaded into Imagix 4D with the -nosys option disabled and the -nosysbodies option enabled.

"MISRA", "MISRA C" and the triangle logo are registered trademarks owned by HORIBA MIRA Ltd, held on behalf of the MISRA Consortium.

MISRA C Directives

Dir.1.1 ⚯Any implementation-defined behavior on which the output of the program depends shall be documented and understood
Dir.2.1 ⚯All source files shall compile without any compilation errors
Dir.3.1 ⚯All code shall be tracable to documented requirements
Dir.4.1 ☑Run-time failure shall be minimized
Dir.4.2 ⚯All usage of assembly language should be documented
Dir.4.3Assembly language shall be encapsulated and isolated
Dir.4.4 ☑Sections of code should not be "commented out"
Dir.4.5 ☑Identifiers in the same name space with overlapping visibility should be typographically unambiguous
Dir.4.6Typedefs that indicate size and signedness should be used in place of the basic numerical types
Dir.4.7 ☑If a function returns error information, then that error information shall be tested
Dir.4.8If a pointer to a structure or union is never dereferenced within a translation unit, then the implementation of the object should be hidden
Dir.4.9 ☑A function should be used in preference to a function-like macro where they are interchangeable
Dir.4.10Precautions shall be taken in order to prevent the contents of a header file being included more than once
Dir.4.11 ☑The validity of values passed to library functions shall be checked
Dir.4.12 ☑Dynamic memory allocation shall not be used
Dir.4.13 ☑Functions which are designed to provide operations on a resource should be called in an appropriate sequence

MISRA C Rules

Rule.1.1 ⚯The program shall contain no violations of the standard C syntax and constraints, and shall not exceed the implementation's translation limits
Rule.1.2 ☑Language extension should not be used
Rule.1.3 ☑There shall be no occurrence of undefined or critical unspecified behaviour
Rule.2.1 ☑A project shall not contain unreachable code
Rule.2.2 ☑There shall be no dead code
Rule.2.3A project shall not contain unused type declarations
Rule.2.4A project should not contain unused tag declarations
Rule.2.5A project should not contain unused macro definitions
Rule.2.6A function should not contain unused label declarations
Rule.2.7There should be no unused parameters in functions
Rule.3.1The character sequences /* and // shall not be used within a comment
Rule.3.2Line-splicing shall not be used in // comments
Rule.4.1Octal and hexadecimal escap sequences shall be terminated
Rule.4.2Trigraphs should not be used
Rule.5.1External identifiers shall be distinct
Rule.5.2Identifiers declared in the same scope and name space shall be distinct
Rule.5.3An identifier declared in an inner scope shall not hide an identifier declared in an outer scope
Rule.5.4Macro identifiers shall be distinct
Rule.5.5Identifiers shall be distinct from macro names
Rule.5.6A typedef name shall be a unique identifier
Rule.5.7A tag name shall be a unique identifier
Rule.5.8Identifiers that define objects or functions with external linkage shall be unique
Rule.5.9Identifiers that define objects or functions with internal linkage shall be unique
Rule.6.1Bit-fields shall only be declared with an appropriate type
Rule.6.2Single-bit named bit fields shall not be of a signed type
Rule.7.1Octal constants shall not be used
Rule.7.2A "u" or "U" suffix shall be applied to all integer constants that are represented in an unsigned type
Rule.7.3The lowercase character "l" shall not be used in a literal suffix
Rule.7.4A string literal shall not be assigned to an object unless the object type is "pointer to const-qualified char"
Rule.8.1Types shall be explicitly specified
Rule.8.2Function types shall be in prototype form with names parameters
Rule.8.3All declarations of an object or function shall use the same names and type qualifiers
Rule.8.4A compatible declaration shall be visible when an object or function with external linkage is defined
Rule.8.5An external object or function shall be declared once in one and only one file
Rule.8.6An identifier with external linkage shall have exactly one external definition
Rule.8.7Functions and objects should not be defined be defined with external linkage if they are referenced in only one translation unit
Rule.8.8The static storage class specifier shall be used in all declarations of objects and functions that have internal linkage
Rule.8.9An object should be defined at block scope if its identifier only appears in a single function
Rule.8.10An inline function shall be declared with the static storage class
Rule.8.11When an array with external linkage is declared, its size should be explicitly specified
Rule.8.12Within an enumerator list, the value of an implicitly-specified enumeration constant shall be unique
Rule.8.13 ☑A pointer should point to a const-qualified type whenever possible
Rule.8.14The restrict type qualifier shall not be used
Rule.9.1 ☑The value of an object with automatic storage duration shall not be read before it has been set
Rule.9.2The initializer for an aggregate or union shall be enclosed in braces
Rule.9.3Arrays shall not be partially initialized
Rule.9.4An element of an object shall not be initialized more than once
Rule.9.5Where designated initializers are used to initialize an array object the size of the array shall be specified explicitly
Rule.10.1Operands shall not be of an inappropriate essential type
Rule.10.2Expressions of essentially character type shall not be used inappropriately in addition and subtraction operations
Rule.10.3The value of an expression shall not be assigned to an object with a narrower essential type of a different essential type category
Rule.10.4Both operands of an operator in which the usual arithmetic conversions are performed shall have the same essential type category
Rule.10.5The value of an expression should not be cast to an inappropriate essential type
Rule.10.6The value of a composite expression shall not be assigned to an object with wider essential type
Rule.10.7If 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
Rule.10.8The value of a composite expression shall not be cast to a different essential type category or a wider essential type
Rule.11.1Conversions shall not be performed between a pointer to a function and any other type
Rule.11.2Conversions shall not be performed between a pointer to an incomplete type and any other type
Rule.11.3A cast shall not be performed between a pointer to object type and a pointer to a different object type
Rule.11.4A conversion should not be performed between a pointer to object type and an integer type
Rule.11.5A conversion should not be performed from pointer to void into pointer to object
Rule.11.6A cast shall not be performed between pointer to void and an arithmetic type
Rule.11.7A cast shall not be performed between pointer to object and a non-integer arithmetic type
Rule.11.8A cast shall not remove any const or volatile qualification from the type pointed to by a pointer
Rule.11.9The macro NULL shall be the only permitted form of integer null pointer constant
Rule.12.1The precedence of operators within expressions should be made explicit
Rule.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
Rule.12.3The comma operator should not be used
Rule.12.4Evaluation of constant expressions should not lead to unsigned integer wrap-around
Rule.13.1 ☑Initializer lists shall not contain persistent side effects
Rule.13.2 ☑The value of an expression and its persistent side effects shall be the same under all permitted evaluation orders
Rule.13.3A full expression containing an increment (++) or decrement (––) operator should have no other potential side effects other than that caused by the increment or decrement operator
Rule.13.4The result of an assignment operator should not be used
Rule.13.5 ☑The right hand operand of a logical && or || operator shall not contain persistent side effects
Rule.13.6The operand of the sizeof operator shall not contain any expression which has potential side effects
Rule.14.1 ☑A loop counter shall not have essentially floating type
Rule.14.2 ☑A for loop shall be well-formed
Rule.14.3 ☑Controlling expressions shall not be invariant
Rule.14.4The controlling expression of an if statement and the controlling expression of an iteration-statement shall have essentially Boolean type
Rule.15.1The goto statement should not be used
Rule.15.2The goto statement shall jump to a label declared later in the same function
Rule.15.3Any label referenced by a goto statement shall be declared in the same block, or in any block enclosing the goto statement
Rule.15.4There should be no more than one break or goto statement used to terminate any iteration statement
Rule.15.5A function should have a single point of exit at the end
Rule.15.6The body of an iteration-statement or a selection-statement shall be a compound-statement
Rule.15.7All if...else if constructs shall be terminated with an else statement
Rule.16.1All switch statements shall be well-formed
Rule.16.2A switch label shall only be used when the most closely-enclosing compund statement is the body of a switch statement
Rule.16.3An unconditional break statement shall terminate every switch-clause
Rule.16.4Every switch statement shall have a default label
Rule.16.5A default label shall appear as either the first or the last switch label of a switch statement
Rule.16.6Every switch statement shall have at least two switch-clauses
Rule.16.7A switch-expression shall not have essentially Boolean type
Rule.17.1The features of <stdarg.h> shall not be used
Rule.17.2 ☑Functions shall not call themselves, either directly or indirectly
Rule.17.3A function shall not be declared implicitly
Rule.17.4All exit paths from a function with non-void return type shall have an explicit return statement with an expression
Rule.17.5 ☑The function argument corresponding to a parameter declared to have an array type shall have an appropriate numebr of elements
Rule.17.6The declaration of an array parameter shall not contain the static keyword between the [ ]
Rule.17.7The value returned by a function having non-void return type shall be used
Rule.17.8 ☑A function parameter should not be modified
Rule.18.1 ☑A pointer resulting from arithmetic on a pointer operand shall address an element of the same array as that pointer operand
Rule.18.2 ☑Subtraction between pointers shall only be applied to pointers that address elements of the same array
Rule.18.3 ☑The relational operators >, >=, < and <= shall not be applied to objects of pointer type except where they point into the same object
Rule.18.4The +, –, += and –= operators should not be applied to an expression of pointer type
Rule.18.5Declarations should contain no more than two levels of pointer nesting
Rule.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
Rule.18.7Flexible array members shall not be declared
Rule.18.8Variable-length array types shall not be used
Rule.19.1 ☑An object shall not be assigned or copied to an overlapping object
Rule.19.2The union keyword should not be used
Rule.20.1#include directives should only be preceded by preprocessor directives or comments
Rule.20.2The ', " or \ characters and the /* or // character sequences shall not occur in a header file name
Rule.20.3The #include directive shall be followed by either a <filename> or "filename" sequence
Rule.20.4A macro shall not be defined with the same name as a keyword
Rule.20.5#undef should not be used
Rule.20.6Tokens that look like a preprocessing directive shall not occur within a macro argument
Rule.20.7Expressions resulting from the expansion of macro parameters shall be enclosed in parentheses
Rule.20.8The controlling expression of a #if or #elif preprocessing directive shall evaluate to 0 or 1
Rule.20.9All identifiers used in the controlling expressions of #if or #elif preprocessing directives shall be #define'd before evaluation
Rule.20.10The # and ## preprocessor operators should not be used
Rule.20.11A macro parameter immediately following a # operator shall not immediately be followed by a ## operator
Rule.20.12A 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
Rule.20.13A line whose first token is # shall be a valid preprocessing directive
Rule.20.14All #else, #elif and #endif preprocessor directives shall reside in the same file as the #if, #ifdef, or #ifndef directive to which they are related
Rule.21.1#define and #undef shall not be used on a reserved identifier or reserved macro name
Rule.21.2A reserved identifier or macro name shall not be declared
Rule.21.3The memory allocation and deallocation functions of <stdlib.h> shall not be used
Rule.21.4The standard header file <setjmp.h> shall not be used
Rule.21.5The standard header file <signal.h> shall not be used
Rule.21.6The Standard Library input/output functions shall not be used
Rule.21.7The atof, atoi and atoll functions of <stdlib.h> shall not be used
Rule.21.8The library functions abort, exit, getenv and system of <stdlib.h> shall not be used
Rule.21.9The library functions bsearch and qsort of <stdlib.h> shall not be used
Rule.21.10The Standard Library time and date functions shall not be used
Rule.21.11The standard header file <tgmath.h> shall not be used
Rule.21.12The exception handling features of <fenv.h> should not be used
Rule.22.1 ☑All resource obtained dynamically by means of Standard Library functions shall be explicitly released
Rule.22.2 ☑A block of memory shall only be freed if it was allocated by means of a Standard Library function
Rule.22.3 ☑The same file shall not be open for read and write access at the same time on different streams
Rule.22.4 ☑There shall be no attempt to write to a stream which has been opened as read-only
Rule.22.5 ☑A pointer to a FILE object shall not be dereferenced
Rule.22.6 ☑The value of a pointer to a FILE shall not be used after the associated stream has been closed