Joined: 07 Nov 2005 Posts: 1105 Location: The Netherlands at Hole 19
From the fine manual (top line / manuals / PLI):
The DEFAULT(ORDER) option indicates that the ORDER option is applied to every block, meaning that variables in that block referenced in ON-units (or blocks dynamically descendant from ON-units) have their latest values. This effectively prohibits almost all optimization on such variables. Consequently, if your program logic allows, use DEFAULT(REORDER) to generate superior code.