MISRA C:2023 enforcement

Summary Total
(a) Total Number of Rules 221
(b) Total Number of ‘Not Statically Enforceable’ Rules (Assisted/Unassisted) 21
(c) Total Number of Enforceable Rules (a-b) 200
(d) Total Number of Enforced Rules 193
(e) Total Number of Unenforced Rules 7
(f) Enforce Rules Percentage (d/c) 96%
(g) Unenforced Rules Percentage (e/c) 4%
Rule Description Category 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 Yes
1.2 Language extensions should not be used. Advisory Yes
1.3 There shall be no occurrence of undefined or critical unspecified behaviour. Required Yes
1.4 Emergent language features shall not be used. Required Yes
1.5 Obsolescent language features shall not be used Required Yes
2.1 A project shall not contain unreachable code. Required Yes
2.2 There shall be no dead code. Required Yes
2.3 A project should not contain unused type declarations. Advisory Yes
2.4 A project should not contain unused tag declarations. Advisory Yes
2.5 A project should not contain unused macro definitions. Advisory Yes
2.6 A function should not contain unused label declarations. Advisory Yes
2.7 There should be no unused parameters in functions. Advisory Yes
2.8 A project should not contain unused object definitions Advisory Yes
3.1 The character sequences /* and // shall not be used within a comment. Required Yes
3.2 Line-splicing shall not be used in // comments. Required Yes
4.1 Octal and hexadecimal escape sequences shall be terminated. Required Yes
4.2 Trigraphs should not be used. Advisory Yes
5.1 External identifiers shall be distinct. Required Yes
5.2 Identifiers declared in the same scope and name space shall be distinct. Required Yes
5.3 An identifier declared in an inner scope shall not hide an identifier declared in an outer scope. Required Yes
5.4 Macro identifiers shall be distinct. Required Yes
5.5 Identifiers shall be distinct from macro names. Required Yes
5.6 A typedef name shall be a unique identifier. Required Yes
5.7 A tag name shall be a unique identifier. Required Yes
5.8 Identifiers that define objects or functions with external linkage shall be unique. Required Yes
5.9 Identifiers that define objects or functions with internal linkage should be unique. Advisory Yes
6.1 Bit-fields shall only be declared with an appropriate type. Required Yes
6.2 Single-bit named bit fields shall not be of a signed type. Required Yes
6.3 A bit field shall not be declared as a member of a union Required Yes
7.1 Octal constants shall not be used. Required Yes
7.2 A "u" or "U" suffix shall be applied to all integer constants that are represented in an unsigned type. Required Yes
7.3 The lowercase character "l" shall not be used in a literal suffix. Required 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 Yes
7.5 The argument of an integer-constant macro shall have an appropriate form Mandatory Yes
7.6 The small integer variants of the minimum-width integer constant macros shall not be used Required Yes
8.1 Types shall be explicitly specified. Required Yes
8.2 Function types shall be in prototype form with named parameters. Required Yes
8.3 All declarations of an object or function shall use the same names and type qualifiers. Required Yes
8.4 A compatible declaration shall be visible when an object or function with external linkage is defined. Required Yes
8.5 An external object or function shall be declared once in one and only one file. Required Yes
8.6 An identifier with external linkage shall have exactly one external definition. Required Yes
8.7 Functions and objects should not be defined with external linkage if they are referenced in only one translation unit. Advisory Yes
8.8 The static storage class specifier shall be used in all declarations of objects and functions that have internal linkage. Required Yes
8.9 An object should be defined at block scope if its identifier only appears in a single function. Advisory Yes
8.10 An inline function shall be declared with the static storage class. Required Yes
8.11 When an array with external linkage is declared, its size should be explicitly specified. Advisory Yes
8.12 Within an enumerator list, the value of an implicitly-specified enumeration constant shall be unique. Required Yes
8.13 A pointer should point to a const-qualified type whenever possible. Advisory Yes
8.14 The restrict type qualifier shall not be used. Required Yes
8.15 All declarations of an object with an explicit alignment specification shall specify the same alignment. Required Yes
8.16 The alignment specification of zero should not appear in an object declaration. Advisory No
8.17 At most one explicit alignment specifier should appear in an object declaration. Advisory No
9.1 The value of an object with automatic storage duration shall not be read before it has been set. Mandatory Yes
9.2 The initializer for an aggregate or union shall be enclosed in braces. Required Yes
9.3 Arrays shall not be partially initialized. Required Yes
9.4 An element of an object shall not be initialized more than once. Required Yes
9.5 Where designated initializers are used to initialize an array object the size of the array shall be specified explicitly. Required Yes
9.6 An initializer using chained designators shall not contain initializers without designators Required Yes
9.7 Atomic objects shall be appropriately initialized before being accessed Mandatory Yes
10.1 Operands shall not be of an inappropriate essential type. Required Yes
10.2 Expressions of essentially character type shall not be used inappropriately in addition and subtraction operations. Required 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 Yes
10.4 Both operands of an operator in which the usual arithmetic conversions are performed shall have the same essential type category. Required Yes
10.5 The value of an expression should not be cast to an inappropriate essential type. Advisory Yes
10.6 The value of a composite expression shall not be assigned to an object with wider essential type. Required 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 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 Yes
11.1 Conversions shall not be performed between a pointer to a function and any other type. Required Yes
11.2 Conversions shall not be performed between a pointer to an incomplete type and any other type. Required Yes
11.3 A cast shall not be performed between a pointer to object type and a pointer to a different object type. Required Yes
11.4 A conversion should not be performed between a pointer to object and an integer type. Advisory Yes
11.5 A conversion should not be performed from pointer to void into pointer to object. Advisory Yes
11.6 A cast shall not be performed between pointer to void and an arithmetic type. Required Yes
11.7 A cast shall not be performed between pointer to object and a noninteger arithmetic type. Required Yes
11.8 A cast shall not remove any const or volatile qualification from the type pointed to by a pointer. Required Yes
11.9 The macro NULL shall be the only permitted form of integer null pointer constant. Required Yes
11.10 The _Atomic qualifier shall not be applied to the incomplete type void. Required Yes
12.1 The precedence of operators within expressions should be made explicit. Advisory 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 Yes
12.3 The comma operator should not be used. Advisory Yes
12.4 Evaluation of constant expressions should not lead to unsigned integer wrap-around. Advisory Yes
12.5 The sizeof operator shall not have an operane which is a function parameter declared as 'array of type'. Mandatory Yes
12.6 Structure and union members of atomic objects shall not be directly accessed Required Yes
13.1 Initializer lists shall not contain persistent side-effects. Required Yes
13.2 The value of an expression and its persistent side effects shall be the same under all permitted evaluation orders and shall be independent from thread interleaving Required 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 Yes
13.4 The result of an assignment operator should not be used. Advisory Yes
13.5 The right hand operand of a logical && or || operator shall not contain persistent side effects. Required Yes
13.6 The operand of the sizeof operator shall not contain any expression which has potential side-effects. Required Yes
14.1 A loop counter shall not have essentially floating type. Required Yes
14.2 A for loop shall be well-formed.. Required Yes
14.3 Controlling expressions shall not be invariant. Required Yes
14.4 The controlling expression of an if-statement and the controlling expression of an iteration-statement shall have essentially Boolean type. Required Yes
15.1 The goto statement should not be used. Advisory Yes
15.2 The goto statement shall jump to a label declared later in the same function. Required 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 Yes
15.4 There should be no more than one break or goto statement used to terminate any iteration statement. Advisory Yes
15.5 A function should have a single point of exit at the end. Advisory Yes
15.6 The body of an iteration-statement or a selection-statement shall be a compound-statement. Required Yes
15.7 All if ... else if constructs shall be terminated with an else statement. Required Yes
16.1 All switch statements shall be well-formed. Required 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 Yes
16.3 An unconditional break statement shall terminate every switch clause. Required Yes
16.4 Every switch statement shall have a default label. Required Yes
16.5 A default label shall appear as either the first or the last switch label of a switch statement. Required Yes
16.6 Every switch statement shall have at least two switch clauses. Required Yes
16.7 A switch-expression shall not have essentially Boolean type. Required Yes
17.1 The features of <stdarg.h> shall not be used. Required Yes
17.2 Functions shall not call themselves, either directly or indirectly. Required Yes
17.3 A function shall not be declared implicitly. Mandatory Yes
17.4 All exit paths from a function with non-void return type shall have an explicit return statement with an expression. Mandatory Yes
17.5 The function argument corresponding to a parameter declared to have an array type shall have an appropriate number of elements. Required Yes
17.6 The declaration of an array parameter shall not contain the static keyword between the [ ]. Mandatory Yes
17.7 The value returned by a function having non-void return type shall be used. Required Yes
17.8 A function parameter should not be modified. Advisory Yes
17.9 A function declared with a _Noreturn function specifier shall not return to its caller Mandatory Yes
17.10 A function declared with a _Noreturn function specifier shall have void return type Required Yes
17.11 A function that never returns should be declared with a _Noreturn function specifier Advisory No
17.12 A function identifier should only be used with either a preceding &, or with a parenthesised parameter list Advisory Yes
17.13 A function type shall not be type qualified Required 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 Yes
18.2 Subtraction between pointers shall only be applied to pointers that address elements of the same array. Required 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 Yes
18.4 The +, -, += and -= operators should not be applied to an expression of pointer type. Advisory Yes
18.5 Declarations should contain no more than two levels of pointer nesting. Advisory Yes
18.6 The address of an object with automatic or thread-local storage shall not be copied to another object that persists after the first object has ceased to exist. Required Yes
18.7 Flexible array members shall not be declared. Required Yes
18.8 Variable-length arrays shall not be used. Required Yes
18.9 An object with temporary lifetime shall not undergo array-to-pointer conversion Required Yes
18.10 Pointers to variably-modified array types shall not be used Mandatory Yes
19.1 An object shall not be assigned or copied to an overlapping object. Mandatory Yes
19.2 The union keyword should not be used. Advisory Yes
20.1 #include directives should only be preceded by preprocessor directives or comments. Advisory Yes
20.2 The ', " or \ characters and the /* or // character sequences shall not occur in a header file name. Required Yes
20.3 The #include directive shall be followed by either a <filename> or "filename" sequence. Required Yes
20.4 A macro shall not be defined with the same name as a keyword. Required Yes
20.5 #undef should not be used. Advisory Yes
20.6 Tokens that look like a preprocessing directive shall not occur within a macro argument. Required Yes
20.7 Expressions resulting from the expansion of macro parameters shall be enclosed in parentheses. Required Yes
20.8 The controlling expression of a #if or #elif preprocessing directive shall evaluate to 0 or 1. Required Yes
20.9 All identifiers used in the controlling expression of #if or #elif preprocessing directives shall be #define'd before evaluation. Required Yes
20.10 The # and ## preprocessor operators should not be used. Advisory Yes
20.11 A macro parameter immediately following a # operator shall not immediately be followed by a ## operator. Required 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 Yes
20.13 A line whose first token is # shall be a valid preprocessing directive. Required 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 Yes
21.1 #define and #undef shall not be used on a reserved identifier or reserved macro name. Required Yes
21.2 A reserved identifier or macro name shall not be declared. Required Yes
21.3 The memory allocation and deallocation functions of <stdlib.h> shall not be used. Required Yes
21.4 The standard header file <setjmp.h> shall not be used. Required Yes
21.5 The standard header file <signal.h> shall not be used. Required Yes
21.6 The Standard Library input/output functions shall not be used. Required Yes
21.7 The atof, atoi, atol and atoll functions of <stdlib.h> shall not be used. Required Yes
21.8 The Standard Library termination functions of <stdlib.h> shall not be used. Required Yes
21.9 The library functions bsearch and qsort of <stdlib.h> shall not be used. Required Yes
21.10 The Standard Library time and date functions shall not be used. Required Yes
21.11 The standard header file <tgmath.h> should not be used. Advisory Yes
21.12 The standard header file <fenv.h> shall not be used. Required Yes
21.13 Any value passed to a function in <ctype.h> shall be representable as an unsigned char or be the value EOF. Mandatory Yes
21.14 The Standard Library function memcmp shall not be used to compare null terminated strings. Required 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 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 Yes
21.17 Use of the string handling functions from <string.h> shall not result in accesses beyond the bounds of the objects referenced by their pointer parameters. Mandatory Yes
21.18 The size_t argument passed to any function in <string.h> shall have an appropriate value. Mandatory 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 Yes
21.20 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 Yes
21.21 The Standard Library function system of <stdlib> shall not be used. Required Yes
21.22 All operand arguments to any type-generic macros declared in <tgmath.h> shall have an appropriate essential type Mandatory Yes
21.23 All operand arguments to any multi-argument type-generic macros declared in <tgmath.h> shall have the same standard type Required Yes
21.24 The random number generator functions of <stdlib.h> shall not be used. Required Yes
21.25 All memory synchronization operations shall be executed in sequentially consistent order Required Yes
21.26 The Standard Library function mtx_timedlock() shall only be invoked on mutex objects of appropriate mutex type Required Yes
22.1 All resources obtained dynamically by means of Standard Library functions shall be explicitly released. Required Yes
22.2 A block of memory shall only be freed if it was allocated by means of a Standard Library function. Mandatory Yes
22.3 The same file shall not be open for read and write access at the same time on different streams. Required Yes
22.4 There shall be no attempt to write to a stream which has been opened as read-only. Mandatory Yes
22.5 A pointer to a FILE object shall not be dereferenced. Mandatory Yes
22.6 The value of a pointer to a FILE shall not be used after the associated stream has been closed. Mandatory Yes
22.7 The macro EOF shall on ly be compared with the unmodified return value from any Standard Library function capable of returning EOF. Required Yes
22.8 The value of errno shall be set to zero prior to a call to an errno-setting-function. Required Yes
22.9 The value of errno shall be tested against zero after calling an errno-setting-function. Required Yes
22.10 The value of errno shall only be tested when the last function to be called was an errnosetting- function. Required Yes
22.11 A thread that was previously either joined or detached shall not be subsequently joined nor detached Required Yes
22.12 Thread objects, thread synchronization objects, and thread-specific storage pointers shall only be accessed by the appropriate Standard Library functions Mandatory Yes
22.13 Thread objects, thread synchronization objects and thread-specific storage pointers shall have appropriate storage duration Required Yes
22.14 Thread synchronization objects shall be initialized before being accessed Mandatory Yes
22.15 Thread synchronization objects and thread-specific storage pointers shall not be destroyed until after all threads accessing them have terminated Required Yes
22.16 All mutex objects locked by a thread shall be explicitly unlocked by the same thread Required Yes
22.17 No thread shall unlock a mutex or call cnd_wait() or cnd_timedwait() for a mutex it has not locked before Required Yes
22.18 Non-recursive mutexes shall not be recursively locked Required Yes
22.19 A condition variable shall be associated with at most one mutex object Required Yes
22.20 Thread-specific storage pointers shall be created before being accessed Mandatory Yes
23.1 A generic selection should only be expanded from a macro Advisory No
23.2 A generic selection that is not expanded from a macro shall not contain potential side effects in the controlling expression Required Yes
23.3 A generic selection should contain at least one non-default association Advisory No
23.4 A generic association shall list an appropriate type Required Yes
23.5 A generic selection should not depend on implicit pointer type conversion Advisory No
23.6 The controlling expression of a generic selection shall have an essential type that matches its standard type Required Yes
23.7 A generic selection that is expanded from a macro should evaluate its argument only once Advisory No
23.8 A default association shall appear as either the first or the last association of a generic selection Required Yes
Directive 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
3.1 All code shall be traceable to documented requirements Required Unassisted
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 Assisted
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 Assisted
4.9 A function should be used in preference to a function-like macro where they are interchangeable Advisory Unassisted
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
4.15 Evaluation of floating-point expressions shall not lead to the undetected generation of infinities and NaNs Required Unassisted
5.1 There shall be no data races between threads Required Unassisted
5.2 There shall be no deadlocks between threads Required Unassisted
5.3 There shall be no dynamic thread creation Required Unassisted

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