Compiler Warning C0540
Message: Attribute 'no_assign' missing for POU '<POU>'. The type of the variable '<variable>' is attributed with 'no_assign'.
Possible error cause: A POU X contains a variable, whose type (POU Y) has the 'no_assign' attribute. POU X has no 'no_assign' attribute.
Error correction: Also decorate the POU with the 'no_assign' attribute.
Example 489. Example of the warning
{attribute 'no_assign'}
FUNCTION_BLOCK FB_NotAssignable
VAR
pBool : POINTER TO BOOL;
END_VAR
FUNCTION_BLOCK FB_WrapperOfNotAssignable
VAR
fbNotAssingable : FB_NotAssignable;
END_VAR
The declaration of the variable fbNotAssignable produces the following warning.
Message:
C0540: Attribute 'no_assign' missing for POU 'FB_WrapperOfNotAssignable'. The type of the variable 'fbNotAssingable' is attributed with 'no_assign'.
Error correction: Also decorate the FB_WrapperOfNotAssignable POU with the 'no_assign' attribute.