Erroneous access to arrays of variable length during online monitoring and forcing (corrected from V3.24)

?Corrected from:
PLC Designer V3.24

Response of the new version:
The online monitoring of the PLC Designer accesses the correct memory area for arrays with variable length (ARRAY[*] OF data type).
 
What happens?
The online monitoring of the PLC Designer accesses the wrong memory area for arrays with variable length (ARRAY[*] OF data type). This means that the value of another array element or even the value of a memory location outside the array is displayed by the PLC Designer. 
When forcing (online value change, menu command 'Debug' > 'Write values' or 'Debug' > 'Force values') an element of an array with variable length, the value of another array element or the variable memory outside the array is changed.

When does the behaviour occur?
The behaviour occurs when variable-length arrays that do not start with index 0 are accessed during online monitoring. It does not matter where the online value is displayed, in the editor, in a monitoring list,...
 
Which products are affected?
PLC Designer from V3.0

Short-term measures:
Do not change (force) the value of an element of a variable-length array.
When observing the value of an element of a variable-length array, take into account that this value is not displayed correctly.
 
Evaluation / recommendations:
Writing values to variable length arrays during online monitoring can change other variables, which can lead to unpredictable behaviour.
The actual processing of the PLC logic is not affected by this function restriction.

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