LANG.ID.NU.EXT : Non-unique Identifiers: External Name

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CodeSonar^® 9.2p0

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C and C++

LANG.ID.NU.EXT : Non-unique Identifiers: External Name

Summary

An identifier with external linkage is identical to one or more other identifiers.

See Identifier Classes for related warning classes.

Properties

Class Name

Non-unique Identifiers: External Name

Significance

style

Mnemonic

LANG.ID.NU.EXT

Categories

MisraC2025	MisraC2025:5.8	Identifiers that define objects or functions with external linkage shall be unique
MisraC2023	MisraC2023:5.8	Identifiers that define objects or functions with external linkage shall be unique
Misra2012	Misra2012:5.8	Identifiers that define objects or functions with external linkage shall be unique
Misra2004	Misra2004:5.5	No object or function identifier with static storage duration should be reused
CWE	CWE:710	Improper Adherence to Coding Standards
CERT-C	CERT-C:DCL23-C	Guarantee that mutually visible identifiers are unique

Availability

Available for C and C++.

Enabling

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

WARNING_FILTER += allow class="Non-unique Identifiers: External Name"

Example

Suppose fileA.c and fileB.c are both in the analyzed software (but not necessarily in the same compilation unit).

/* LANG.ID.NU.EXT.a.c */

#define externA 1
typedef int externB;
static void externC(void);

/* LANG.ID.NU.EXT.b.c */

extern int externA;            /* 'Non-unique Identifiers: External Name' warning issued here */
extern int externB;            /* 'Non-unique Identifiers: External Name' warning issued here */
extern int externC;            /* 'Non-unique Identifiers: External Name' warning issued here */

Relevant Configuration File Parameters

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

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