LANG.STRUCT.DECL.IMPFN : Implicit Function Declaration

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CodeSonar^® 9.2p0

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C and C++

LANG.STRUCT.DECL.IMPFN : Implicit Function Declaration

Summary

A function is invoked, but it has not yet been declared.

Properties

Class Name

Implicit Function Declaration

Significance

style

Mnemonic

LANG.STRUCT.DECL.IMPFN

Categories

MisraC2025	MisraC2025:17.3	A function shall not be declared implicitly
MisraC2023	MisraC2023:17.3	A function shall not be declared implicitly
Misra2012	Misra2012:17.3	A function shall not be declared implicitly
Misra2004	Misra2004:8.1	Functions shall have prototype declarations and the prototype shall be visible at both the function definition and call
AUTOSARC++14	AUTOSARC++14:A1-1-1	All code shall conform to ISO/IEC 14882:2014 - Programming Language C++ and shall not use deprecated features.
MisraC++2023	MisraC++2023:4.1.2	Deprecated features should not be used
	MisraC++2023:6.5.1	A function or object with external linkage should be introduced in a header file
CWE	CWE:686	Function Call With Incorrect Argument Type
CERT-C	CERT-C:MSC23-C	Beware of vendor-specific library and language differences

Availability

Available for C and C++.

Enabling

Checks for this warning class are enabled by default. However, warning instances of this class that are issued as parser errors (rather than parser warnings) will be discarded when using factory configuration settings. To prevent these instances from being discarded, add the following WARNING_FILTER rule to the project configuration file.

WARNING_FILTER += allow class="Implicit Function Declaration"

To disable checks for this warning class, add the following WARNING_FILTER rule to the project configuration file.

WARNING_FILTER += discard class="Implicit Function Declaration"

Example

int f(double a);   
 
int lang_struct_decl_impfn_before(double a){
    return f(a);                                          /* f() already declared */             
}
 
int lang_struct_decl_impfn_none(double a){
    return g(a);                 /* 'Implicit Function Declaration' warning issued here
                                  * - g() never declared */
}
 
int lang_struct_decl_impfn_after(double a){
  return h(a);                   /* 'Implicit Function Declaration' warning issued here
                                  * - h() declared after invocation */
}

int h(double a);

Relevant Configuration File Parameters

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

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