HP DDL D40 Reference Manual page 291

DDL Compiler Commands
If the group referred to does not start on a word boundary but is described with a
REDEFINES clause, DDL inserts a filler byte before the group being redefined.
FILLER Command Example
The filler algorithm you select affects the structure of the source code; for example,
consider the following DEFINITION statements:
DEF test1.
02 a
02 b
END
DEF case1.
02 c
02 test1
END
DEF case2.
02 test1
02 c
END
With FILLER 1, the COBOL source code for CASE1 and CASE2 is:
01 CASE1.
02 C
02 FILLER
02 TEST1.
03 A
03 B
01 CASE2.
02 TEST1.
03 A
03 B
02 C
With FILLER 0, the COBOL code is:
01 CASE1.
02 C
02 TEST1.
03 A
03 FILLER
03 B
01 CASE2.
02 TEST1.
03 A
03 B
02 C
Data Definition Language (DDL) Reference Manual—426798-002
PIC XX.
PIC S9(4)
PIC X.
TYPE *.
TYPE *.
PIC X.
PIC X.
PIC X(1).
PIC XX.
PIC S9(4)
PIC XX.
PIC S9(4)
PIC X.
PIC X.
PIC XX.
PIC X(1).
PIC S9(4)
PIC XX.
PIC S9(4)
PIC X.
9- 61
COMP.
COMP.
COMP.
COMP.
COMP.
FILLER Command