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SA0015: Access to global data via FB_Init

Detects the access of a function block to global variables by means of the method FB_Init. The value of this variable depends on the order of initializations.

Justification: Depending on the declaration location of the POU instance, an uninitialized variable could be accessed if the rule is violated.

Importance: High

Example 28. Example
VAR_GLOBAL
    g_xTest1 : BOOL;
    g_iTest3 : INT;
END_VAR
METHOD PUBLIC fb_init : BOOL
VAR_INPUT
    (* If TRUE, the retain variables are initialized (warm start / cold start) *)
    bInitRetains : BOOL; 
    (* If TRUE, the instance afterwards gets moved into the copy code (online change) *)
    bInCopyCode : BOOL;  
END_VAR

g_xTest1 := NOT g_xTest1;       // SA0015
g_iTest3 := g_iTest3 + INT#1;   // SA0015

Output in the Messages view:

  • sa_icon_message.png SA0015: FB_Init method of function block 'POU' accesses global data



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