If, when using binary data items (that is, RM/COBOL COMPUTATIONAL-1 format items) an arithmetic operation gives a value which exceeds the capacity of the data item, and there is no ON SIZE ERROR clause, Visual COBOL wraps-around the value of the item. However, in RM/COBOL, the data item is set to the limit of its capacity.
You should specify an ON SIZE ERROR clause to highlight such problems.
In RM/COBOL, the following lines of code result in the value +32767 being stored in the data item, CALC-ITEM. However, Visual COBOL sets CALC-ITEM to -32768:
01 calc-item pic s9(4) comp-1. procedure division. .... move 32767 to calc-item. add 1 to calc-item.