PERFORM_EXTENSIBILITY_CHECK 1664 src/objects.cc   if (extensibility_check == PERFORM_EXTENSIBILITY_CHECK &&
PERFORM_EXTENSIBILITY_CHECK 1848 src/objects.cc                                               PERFORM_EXTENSIBILITY_CHECK);
PERFORM_EXTENSIBILITY_CHECK 1981 src/objects.h        ExtensibilityCheck extensibility_check = PERFORM_EXTENSIBILITY_CHECK);