Rules supported by RuleChecker

SEI CERT C Coding Standard

Below is the list of SEI CERT C rules and recommendations supported as of RuleChecker 20.10.

Light-colored items are supported either partially or only when using RuleChecker in conjunction with Astrée. Exclamation marks denote recom­men­da­tions that, by definition, cannot be checked for automatically by any tool.

Further details on individual rules are available via RuleChecker’s “Help” menu or by contacting

PRE.0 Prefer inline or static functions to function-like macros
PRE.1 Use parentheses within macros around parameter names
PRE.5 Understand macro replacement when concatenating tokens
or performing stringification
PRE.6 Enclose header files in an inclusion guard
PRE.7 Avoid using repeated question marks
PRE.9 Do not replace secure functions with deprecated or obsolescent functions
PRE.11 Do not conclude macro definitions with a semicolon
PRE.12 Do not define unsafe macros
PRE.30 Do not create a universal character name through concatenation
PRE.32 Do not use preprocessor directives in invocations of function-like macros
Declarations and initialization
DCL.0 Const-qualify immutable objects
DCL.1 Do not reuse variable names in subscopes
DCL.5 Use typedefs of non-pointer types only
DCL.7 Include the appropriate type information in function declarators
DCL.8 Properly encode relationships in constant definitions !
DCL.10 Maintain the contract between the writer and caller of variadic functions
DCL.11 Understand the type issues associated with variadic functions !
DCL.13 Declare function parameters that are pointers to values not changed by the function as const
DCL.15 Declare file-scope objects or functions that do not need external linkage as static
DCL.16 Use L, not l, to indicate a long value
DCL.17 Beware of miscompiled volatile-qualified variables !
DCL.18 Do not begin integer constants with 0 when specifying a decimal value
DCL.19 Minimize the scope of variables and functions
DCL.20 Explicitly specify void when a function accepts no arguments
DCL.21 Understand the storage of compound literals !
DCL.22 Use volatile for data that cannot be cached !
DCL.23 Guarantee that mutually visible identifiers are unique
DCL.30 Declare objects with appropriate storage durations
DCL.31 Declare identifiers before using them
DCL.36 Do not declare an identifier with conflicting linkage classifications
DCL.37 Do not declare or define a reserved identifier
DCL.38 Use the correct syntax when declaring a flexible array member
DCL.40 Do not create incompatible declarations of the same function or object
DCL.41 Do not declare variables inside a switch statement before the first case label
EXP.2 Be aware of the short-circuit behavior of the logical AND and OR operators
EXP.3 Do not assume the size of a structure is the sum of the sizes of its members
EXP.5 Do not cast away a const qualification
EXP.8 Ensure pointer arithmetic is used correctly
EXP.9 Use sizeof to determine the size of a type or variable
EXP.10 Do not depend on the order of evaluation of subexpressions
or the order in which side effects take place
EXP.11 Do not make assumptions regarding the layout of structures with bit-fields
EXP.12 Do not ignore values returned by functions
EXP.13 Treat relational and equality operators as if they were non-associative
EXP.15 Do not place a semicolon on the same line as an if, for, or while statement
EXP.16 Do not compare function pointers to constant values
EXP.19 Use braces for the body of an if, for, or while statement
EXP.20 Perform explicit tests to determine success, true and false, and equality
EXP.30 Do not depend on the order of evaluation for side effects
EXP.32 Do not access a volatile object through a nonvolatile reference
EXP.33 Do not read uninitialized memory
EXP.34 Do not dereference null pointers
EXP.36 Do not cast pointers into more strictly aligned pointer types
EXP.37 Call functions with the correct number and type of arguments
EXP.40 Do not modify constant objects
EXP.42 Do not compare padding data
EXP.43 Avoid undefined behavior when using restrict-qualified pointers
EXP.44 Do not rely on side effects in operands to sizeof, _Alignof, or _Generic
EXP.45 Do not perform assignments in selection statements
EXP.46 Do not use a bitwise operator with a Boolean-like operand
INT.0 Understand the data model used by your implementation(s) !
INT.2 Understand integer conversion rules !
INT.7 Use only explicitly signed or unsigned char type for numeric values
INT.8 Verify that all integer values are in range
INT.9 Ensure enumeration constants map to unique values
INT.12 Do not make assumptions about the type of a plain int bit-field
when used in an expression
INT.13 Use bitwise operators only on unsigned operands
INT.16 Do not make assumptions about representation of signed integers
INT.18 Evaluate integer expressions in a larger size before comparing
or assigning to that size
INT.30 Ensure that unsigned integer operations do not wrap
INT.31 Ensure that integer conversions do not result in lost or misinterpreted data
INT.32 Ensure that operations on signed integers do not result in overflow
INT.33 Ensure that division and remainder operations do not result in divide-by-zero errors
INT.34 Do not shift an expression by a negative number of bits
or by greater than or equal to the number of bits that exist in the operand
INT.35 Use correct integer precisions
INT.36 Converting a pointer to integer or integer to pointer
Floating point
FLP.0 Understand the limitations of floating-point numbers !
FLP.1 Take care in rearranging floating-point expressions !
FLP.2 Avoid using floating-point numbers when precise computation is needed
FLP.3 Detect and handle floating-point errors
FLP.4 Check floating-point inputs for exceptional values
FLP.6 Convert integers to floating point for floating-point operations
FLP.30 Do not use floating-point variables as loop counters
FLP.32 Prevent or detect domain and range errors in math functions
FLP.34 Ensure that floating-point conversions are within range of the new type
FLP.36 Preserve precision when converting integral values to floating-point type
FLP.37 Do not use object representations to compare floating-point values
ARR.0 Understand how arrays work !
ARR.1 Do not apply the sizeof operator to a pointer when taking the size of an array
ARR.2 Explicitly specify array bounds, even if implicitly defined by an initializer
ARR.30 Do not form or use out-of-bounds pointers or array subscripts
ARR.36 Do not subtract or compare two pointers that do not refer to the same array
ARR.37 Do not add or subtract an integer to a pointer to a non-array object
ARR.38 Guarantee that library functions do not form invalid pointers
ARR.39 Do not add or subtract a scaled integer to a pointer
Characters and strings
STR.0 Represent characters using an appropriate type
STR.4 Use plain char for characters in the basic character set
STR.5 Use pointers to const when referring to string literals
STR.9 Don’t assume numeric values for expressions with type plain character
STR.10 Do not concatenate different types of string literals
STR.11 Do not specify the bound of a character array initialized with a string literal
STR.30 Do not attempt to modify string literals
STR.31 Guarantee that storage for strings has sufficient space
for character data and the null terminator
STR.32 Do not pass a non-null-terminated character sequence
to a library function that expects a string
STR.34 Cast characters to unsigned char before converting to larger integer sizes
STR.37 Arguments to character-handling functions must be representable as an unsigned char
STR.38 Do not confuse narrow and wide character strings and functions
Memory management
MEM.1 Store a new value in pointers immediately after free()
MEM.2 Immediately cast the result of a memory-allocation function call into a pointer to the allocated type
MEM.4 Beware of zero-length allocations
MEM.7 Ensure that the arguments to calloc(), when multiplied, do not wrap
MEM.30 Do not access freed memory
MEM.31 Free dynamically allocated memory when no longer needed
MEM.33 Allocate and copy structures containing a flexible array member dynamically
MEM.34 Only free memory allocated dynamically
MEM.35 Allocate sufficient memory for an object
MEM.36 Do not modify the alignment of objects by calling realloc()
FIO.14 Understand the difference between text mode and binary mode with file streams !
FIO.37 Do not assume that fgets() or fgetws()
returns a nonempty string when successful
FIO.38 Do not copy a FILE object
FIO.39 Do not alternately input and output from a stream without an intervening flush or positioning call
FIO.41 Do not call getc(), putc(), getwc() or putwc() with a stream argument that has side effects
FIO.42 Close files when they are no longer needed
ENV.30 Do not modify the object referenced by the return value of certain functions
ENV.33 Do not call system()
SIG.1 Understand implementation-specific details regarding signal handler persistence !
SIG.30 Call only asynchronous-safe functions within signal handlers
SIG.31 Do not access shared objects in signal handlers
SIG.34 Do not call signal() from within interruptible signal handlers
Error handling
ERR.6 Understand the termination behavior of assert() and abort() !
ERR.30 Set errno to zero before calling a library function known to set errno, and check errno only after the function returns a value indicating failure
ERR.33 Detect and handle standard library errors
Application Programming Interfaces (API)
API.8 Avoid parameter names in a function prototype
CON.0 Avoid race conditions with multiple threads
CON.1 Acquire and release synchronization primitives in the same module,
at the same level of abstraction
CON.3 Ensure visibility when accessing shared variables
CON.6 Ensure that every mutex outlives the data it protects
CON.30 Clean up thread-specific storage
CON.31 Do not destroy a mutex while it is locked
CON.32 Prevent data races when accessing bit-fields from multiple threads
CON.33 Avoid race conditions when using library functions
CON.35 Avoid deadlock by locking in a predefined order
CON.37 Do not call signal() in a multithreaded program
CON.39 Do not join or detach a thread that was previously joined or detached
CON.40 Do not refer to an atomic variable twice in an expression
MSC.1 Strive for logical completeness
MSC.4 Use comments consistently and in a readable fashion
MSC.7 Detect and remove dead code
MSC.12 Detect and remove code that has no effect or is never executed
MSC.13 Detect and remove unused values
MSC.15 Do not depend on undefined behavior
MSC.17 Finish every set of statements associated with a case label
with a break statement
MSC.20 Do not use a switch statement to transfer control into a complex block
MSC.21 Use robust loop termination conditions
MSC.23 Beware of vendor-specific library and language differences
MSC.24 Do not use deprecated or obsolescent functions
MSC.30 Do not use the rand() function for generating pseudorandom numbers
MSC.32 Properly seed pseudorandom number generators
MSC.33 Do not pass invalid data to the asctime()function
MSC.37 Ensure that control never reaches the end of a non-void function
MSC.40 Do not violate constraints
Microsoft Windows
WIN.3 Understand HANDLE inheritance !


RuleChecker screenshot

RuleChecker supports MISRA-C:2004, MISRA-C:2012 (including Amend­ments 1 and 2), and MISRA-C++:2008. It is highly configurable, allowing you to check for individual rules and even specific aspects of certain rules.

Between the three rule sets, a total of 474 rules are checked. A 30-page PDF description of how RuleChecker handles each rule is available on request. Contact for your free copy.

Below is just a quick overview of all the supported rule categories.

2Language extensions
4Character sets
8Declarations and definitions
10Arithmetic type conversions
11Pointer type conversions
13Control statement expressions
14Control flow
15Switch statements
17Pointers and arrays
18Structures and unions
19Preprocessing directives
20Standard libraries
21Run-time failures
1A standard C environment
2Unused code
4Character sets and lexical convention
7Literals and constants
8Declarations and definitions
10The essential type model
11Pointer type conversions
13Side effects
14Control statement expressions
15Control flow
16Switch statements
18Pointers and arrays
19Overlapping storage
20Preprocessing directives
21Standard libraries
MISRA-C:2012 Amendment 1
21Standard libraries
MISRA-C:2012 Amendment 2
1A standard C environment
21Standard libraries
0Language-independent issues
2Lexical conventions
3Basic concepts
4Standard conversions
10Derived classes
11Member access control
12Special member functions
15Exception handling
16Preprocessing directives
17Library introduction
18Language support library
19Diagnostics library
27Input/output library

Common Weakness Enumeration (CWE)

Below is the list of supported CWE rules as of RuleChecker 20.10. This includes items with the CWE CCR accuracies Exact, CWE-more-abstract, CWE-more-specific, and CWE-partial.

118Improper access of indexable resource
123Write-what-where condition
124Buffer underwrite
125Out-of-bounds read
126Buffer over-read
127Buffer under-read
129Improper validation of array index
415Double free
456Missing initialization of a variable
457Use of uninitialized variable
467Use of sizeof() on a pointer type
468Incorrect pointer scaling
478Missing default case in switch statement
481Assigning instead of comparing
558Use of getlogin() in multithreaded application
561Dead code
665Improper initialization
676Use of potentially dangerous function
685Function call with incorrect number of arguments
686Function call with incorrect argument type
761Free of pointer not at start of buffer
823Use of out-of-range pointer offset
824Access of uninitialized pointer
908Use of uninitialized resource
The following rules are additionally supported when using RuleChecker in conjunction with Astrée. For further details, see RuleChecker’s “Help”  menu or contact
15External control of system or configuration setting
73External control of file system or path
77Improper neutralization of special elements used in a command (command injection)
78Improper neutralization of special elements used in an OS command (OS-command injection)
79Improper neutralization of input during Web page generation (cross-site scripting)
88Argument injection or modification
89Improper neutralization of special elements used in an SQL command (SQL injection)
90Improper neutralization of special elements used in an LDAP command (LDAP injection)
91XML injection (aka blind XPath injection)
99Improper control of resource identifiers (resource injection)
117Improper output neutralization for logs
119Improper restriction of operations within the bounds of a memory buffer
120Buffer copy without checking size of input (‘classic buffer overflow‘)
121Stack-based buffer overflow
122Heap-based buffer overflow
128Wrap-around error
130Improper handling of length parameter inconsistency
131Incorrect calculation of buffer size
170Improper null termination
188Reliance on data/memory layout
190Integer overflow or wraparound
191Integer underflow or wraparound
193Off-by-one error
194Unexpected sign extension
195Signed to unsigned conversion error
196Unsigned to signed conversion error
197Numeric truncation error
240Improper handling of inconsistent structural elements
242Use of inherently dangerous function
252Unchecked return value
253Incorrect check of function return value
362Concurrent execution using shared resource
with improper synchronization (‘race condition’)
364Signal handler race condition
365Race condition in switch
366Race condition within a thread
367Time-of-check time-of-use (TOCTOU) race condition
369Divde by zero
398Indicator of poor code quality
404Improper resource shutdown or release
411Resource locking problems
415Double free
416Use after free
466Return of pointer value outside of expected range
471Modification of assumed-immutable data (MAID)
475Undefined behavior for input to API
476NULL pointer dereference
567Unsynchronized access to shared data in a multithreaded context
573Improper following of specification by caller
587Assignment of a fixed address to a pointer
588Attempt to access child of a nonstructure pointer
628Function call with incorrectly specified arguments
662Improper synchronization
667Improper locking
672Operation on a resource after expiration or release
680Integer overflow to buffer overflow
681Incorrect conversion between numeric types
682Incorrect calculation
690Unchecked return value to NULL pointer dereference
754Improper check for unusual or exceptional conditions
763Release of invalid pointer or reference
764Multiple locks of a critical resource
765Multiple unlocks of a critical resource
785Use of path manipulation function without maximum-sized buffer
786Access of memory location before start of buffer
787Out-of-bounds write
805Buffer access with incorrect length value
806Buffer access using size of source buffer
825Expired pointer dereference
832Unlock of a resource that is not locked
835Loop with unreachable exit condition (‘infinite loop’)


Below is the list of ISO/IEC rules and diagnostics supported as of RuleChecker 20.10. Further details on individual rules are available via RuleChecker’s “Help” menu or by contacting

ISO/IEC TS 17961:2013 C Secure Coding Rules

accfreeAccessing freed memory
accsigAccessing shared objects in signal handlers
addrescapeEscaping of the address of an automatic object
alignconvConverting pointer values to more strictly aligned pointer types
argcompCalling functions with incorrect arguments
asyncsigCalling functions in the C Standard Library other than abort, _Exit, and signal from within a signal handler
boolasgnNo assignment in conditional expressions.
chrsgnextPassing arguments to character-handling functions that are not representable as unsigned char.
dblfreeFreeing memory multiple times
diverrInteger division errors
filecpyCopying a FILE object
funcdeclDeclaring the same function or object in incompatible ways
insufmemAllocating insufficient memory
intoflowOverflowing signed integers
intptrconvConverting a pointer to integer or integer to pointer
inverrnoIncorrectly setting and using errno
invfmtstrUsing invalid format strings
invptrForming or using out-of-bounds pointers or array subscripts
ioileaveInterleaving stream inputs and outputs without a flush or positioning call
liberrFailing to detect and handle standard library errors
libmodModifying the string returned by getenv, localeconv, setlocale, and strerror
libptrForming invalid pointers by library function
libuseUsing an object overwritten by getenv, localeconv, setlocale, and strerror
nonnullcsPassing a non-null-terminated character sequence to a library function that expects a string
nullrefDereferencing an out-of-domain pointer
padcompComparison of padding data
ptrcompAccessing an object through a pointer to an incompatible type
ptrobjSubtracting or comparing two pointers that do not refer to the same array
residentUsing identifiers that are reserved for the implementation
restrictPassing pointers into the same object as arguments to different restrict-qualified parameters
sigcallCalling signal from interruptible signal handlers
sizeofptrTaking the size of a pointer to determine the size of the pointed-to type
strmodModifying string literals
swtchdfltUse of an implied default in a switch statement
syscallCalling system
taintformatioUsing a tainted value to write to an object using a formatted input or output function
taintnoprotoUsing a tainted value as an argument to an unprototyped function pointer
taintsinkTainted, potentially mutilated, or out-of-domain integer values are used in a restricted sink
taintstrcpyTainted strings are passed to a string copying function
uninitrefReferencing uninitialized memory
usrfmtIncluding tainted or out-of-domain input in a format string
xfileposUsing a value for fsetpos other than a value returned from fgetpos
xfreeReallocating or freeing memory that was not dynamically allocated

ISO/IEC 9899:1999 diagnostics

Constraint violations
6.2.7p2 Two declarations that declare the same entity must be of compatible type
6.2.7p2 At least one type specifier shall be given in a declaration The number of arguments shall agree with the number of parameters
6.5.4p3 No implicit conversion shall be performed between pointer types and integer types If the size expression of an array declarator is constant, it shall have a value greater than zero
6.7.10p2 The constant expression of a static assert shall compare unequal to zero
Language extensions
4p5 Assembler code shall be avoided
4p5 Data placement at an absolute location shall be avoided
4p5 Enums shall not be forward-declared, i.e. used as complete type before being defined
4p5 Lvalue casts shall be avoided
4p5 Non-standard keywords shall not be used
4p5 Pointer attributes shall be avoided
4p5 GCC’s statement expressions shall not be used
6.5.1p2 Implicit function declaration shall not be used
6.6p10 Only integer constant expressions stricly conforming to the C standard shall be used
Implementation-defined behavior No cast shall be performed between pointer types and integer types The value of an integer character constant containing more than one character is implementation-defined
Unspecified behavior
6.5 The result of the evaluation of an expression shall not depend on the order of evaluation of subexpressions
6.7.8 The result of the evaluation of an initializer list expression shall not depend on the order of evaluation of elements and subexpressions


As of release 20.10, RuleChecker supports a total of 239 AUTOSAR C++14 coding rules. A detailed PDF description of how each rule is handled is available on request. Contact for your free copy.

Below is just a quick overview of the currently supported rule categories.

0Language independent issues
2Lexical conventions
3Basic concepts
4Standard conversions
10Derived classes
11Member access control
12Special member functions
15Exception handling
16Preprocessing directives
17Library instruction
18Language support library
19Diagnostics library
27Input/output library


RuleChecker automatically compiles various code metrics. For each metric, you can optionally specify thresholds to check your code against, essentially creating additional rules of your own.

Comment density
Cyclomatic complexity
Number of return statements
Number of goto statements
Number of instructions per function
Number of parameters
Number of maintainable code lines
Maximum nesting of control structures
Maximum number of execution paths
Number of called functions
Number of calling functions
Number of recursive paths
Language scope
Comment density (HIS)

Other rules

Customer-specific rules

We have ample experience with extending RuleChecker for various customers with their very own in-house rule sets. Please contact with any questions.

Style rules

These optional rules cover the naming of all C identifiers. For each kind of identifier, you can specify a maximum and minimum length, and check the spelling using regular expressions.

Function naming
All functions
Global functions
Static functions
Macro naming
All macros
Function-like macros
Object-like macros
Member naming
All members
Struct members
Union members
Object naming
All objects
Global objects
Static objects
Local objects
Tag naming
All tags
Enumeration tags
Struct tags
Union tags
Type naming
All types
Struct types
Enumeration naming
Enumeration constants