SA0073: Use of non-temporary counter variable

Function	Determines the use of non-temporary variables in FOR loops.
Reason	This is a performance warning. A counter variable is always initialized each time a programming block is called. You can create such a variable as a temporary variable (VAR_TEMP). This may result in faster access, and the variable does not occupy permanent storage space.
Importance	Medium
PLCopen rule	CP21/L13

Sample:

PROGRAM MAIN
VAR
    nIndex  : INT;
    nSum    : INT;
END_VAR

FOR nIndex := 1 TO 10 BY 1 DO    // => SA0073 
    nSum := nSum + nIndex;
END_FOR