LANG.STRUCT.DECL.MISSINGDECL : No Previous Declaration

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A function or object with external linkage is defined, but has no visible (non-defining) declaration.

Class Name

No Previous Declaration

Significance

style

Mnemonic

LANG.STRUCT.DECL.MISSINGDECL

Categories

MisraC2023	MisraC2023:8.4	A compatible declaration shall be visible when an object or function with external linkage is defined
Misra2012	Misra2012:8.4	A compatible declaration shall be visible when an object or function with external linkage is defined
Misra2004	Misra2004:8.1	Functions shall have prototype declarations and the prototype shall be visible at both the function definition and call

Availability

Available for C and C++.

Enabling

Checks for this warning class are disabled by default, and require the unnormalized C ASTs for the project. To enable them, add the following WARNING_FILTER rule and RETAIN_UNNORMALIZED_C_AST specification to the project configuration file.

RETAIN_UNNORMALIZED_C_AST = Yes
WARNING_FILTER += allow class="No Previous Declaration"

Note that retaining the unnormalized ASTs will increase the disk space used to store the project representation, and may make the analysis take longer.

extern void f1(void);
void f1(void) {}                          /* ok: previously declared */

static void f2(void) {}                   /* ok: no external linkage */

void f3(void) {}           /* 'No Previous Declaration' warning issued here
                            * - there is no (non-defining) declaration for func3()
                            */

void f4(void) {}           /* 'No Previous Declaration' warning issued here
                            * - there is a declaration, but it is after this definition
                            */
extern void f4(void);

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

LANG.STRUCT.DECL.MISSINGDECL : No Previous Declaration

Summary

Properties

Example

Relevant Configuration File Parameters