The checkNumericOverflow build descriptor option specifies whether the generated code will check for numeric overflow. This option is available for Java™ or COBOL, not for JavaScript.
Not checking for numeric overflow might result in smaller programs with better performance.
If you specify NO, the vgVar.handleOverflow system variable is ignored, and division by zero results in an abend with a message. In other overflow conditions, the result is truncated, causing the significant digits to be lost, but the generated program gives no indication that truncation has occurred.
Design your program such that numeric overflow does not occur.