LANG.CAST.FN : Dangerous Function Cast

JavaScript is not currently enabled, but is required for full CodeSonar manual search and browse functionality.

If you are viewing this file in your hub's Web GUI, enable JavaScript in your browser: you will also need it for GUI functionality.

If you opened this file directly from disk, your browser may be directly suppressing JavaScript functionality: certain browsers perform this suppression on local files (but not files delivered by web servers) for security reasons.

If you access the manual through the hub's Web GUI, the functionality will not be suppressed because the hub is a web server.
Alternatively, your browser may allow you to explicitly disable the security setting that suppresses functionality. See the CodeSonar FAQ for more information.

A function pointer is cast to another function pointer that has an incompatible signature or return type.

Class Name

Dangerous Function Cast

Significance

reliability

Mnemonic

LANG.CAST.FN

Categories

MisraC2023	MisraC2023:1.3	There shall be no occurrence of undefined or critical unspecified behaviour
	MisraC2023:11.1	Conversions shall not be performed between a pointer to a function and any other type
Misra2012	Misra2012:1.3	There shall be no occurrence of undefined or critical unspecified behaviour
	Misra2012:11.1	Conversions shall not be performed between a pointer to a function and any other type
Misra2004	Misra2004:11.1	Conversions shall not be performed between a pointer to a function and any type other than an integral type
AUTOSARC++14	AUTOSARC++14:A5-2-2	Traditional C-style casts shall not be used.
	AUTOSARC++14:M5-2-6	A cast shall not convert a pointer to a function to any other pointer type, including a pointer to function type.
	AUTOSARC++14:M8-4-4	A function identifier shall either be used to call the function or it shall be preceded by &.
MisraC++2008	MisraC++2008:5-2-4	C-style casts (other than void casts) and functional notation casts (other than explicit constructor calls) shall not be used.
	MisraC++2008:5-2-6	A cast shall not convert a pointer to a function to any other pointer type, including a pointer to function type.
	MisraC++2008:8-4-4	A function identifier shall either be used to call the function or it shall be preceded by &.
MisraC++2023	MisraC++2023:4.1.3	There shall be no occurrence of undefined or critical unspecified behaviour
	MisraC++2023:8.2.2	C-style casts and functional notation casts shall not be used
CWE	CWE:704	Incorrect Type Conversion or Cast
JSF++	JSF++:183	Every possible measure should be taken to avoid type casting.

Availability

Available for C and C++.

Enabling

Checks for this warning class are enabled by default. To disable them, add the following WARNING_FILTER rule to the project configuration file.

WARNING_FILTER += discard class="Dangerous Function Cast"

typedef void (*thunk_t)(void);
typedef int (*int_unary_t)(int);
      
void A( void ) {}

int B( int i ) { 
    printf("%d", i); 
    return 1; 
}

void lang_cast_fn(void) {
    thunk_t thunk = (thunk_t)A;
    int_unary_t unary = (int_unary_t)B;
        
    thunk = (thunk_t)unary;  /* 'Dangerous Function Cast' warning issued here */
    thunk();
}

The following configuration file parameters affect checks for this warning class.

LANG.CAST.FN : Dangerous Function Cast

Summary

Properties

Example

See also

Relevant Configuration File Parameters