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HP OpenVMS Systems Documentation |
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HP COBOL
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/STANDARD=V3 evaluation order not supported for this construct |
/STANDARD=V3 variable length item rules not supported for this construct |
For full information on the differences in the HP COBOL for OpenVMS Alpha or the OpenVMS I64 implementation of the /STANDARD=V3 qualifier, refer to the online help.
HP COBOL for OpenVMS VAX Version 5.1 (and higher) provides a flagging system, via the /STANDARD=OPENVMS_AXP qualifier option, to identify language features in your existing programs that are not available in HP COBOL on the OpenVMS Alpha system. (There may be additional language features not available on the Tru64 UNIX system.)
When you specify /STANDARD=OPENVMS_AXP, the HP COBOL for OpenVMS VAX compiler generates informational messages to alert you to language constructs that are not available in HP COBOL on OpenVMS Alpha or OpenVMS I64. (You must also specify /WARNINGS=ALL or /WARNINGS=INFORMATIONAL to receive these messages.) You can use this information to modify your program.
Specify /STANDARD=NOOPENVMS_AXP, which is the default, to suppress
these informational messages.
B.4 HP COBOL Behavior Differences on VAX and Alpha and I64
This section describes behavior differences between HP COBOL on
its Alpha and I64 and VAX platforms.
B.4.1 Program Structure Messages
In some cases, the HP COBOL compiler (whether on the OpenVMS Alpha, OpenVMS I64, or the Tru64 UNIX system) generates more complete messages about unreachable code or other logic errors than does the HP COBOL for OpenVMS VAX compiler.
The following example illustrates a sample program and the messages issued, or not issued, by the HP COBOL compiler on each of the three platforms:
IDENTIFICATION DIVISION.
PROGRAM-ID. T1.
ENVIRONMENT DIVISION.
PROCEDURE DIVISION.
P0.
GO TO P1.
P2.
DISPLAY "This is unreachable code".
P1.
STOP RUN.
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$ COBOL /ANSI/WARNINGS=ALL T1.COB $ |
The program compiles. The HP COBOL for OpenVMS VAX compiler produces no messages.
On OpenVMS Alpha and I64 systems
$ COBOL/ANSI/OPTIMIZE/WARNINGS=ALL T1.COB
P2.
.......^
%COBOL-I-UNREACH, code can never be executed at label P2
at line number 7 in file DISK$YOURDISK:[TESTDIR]T1.COB;1
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% cobol -ansi -O -warn all T1.COB
cobol: Info: T1.COB, line 7: code can never be executed at label P2
P2
-------^
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HP COBOL on either Alpha platform, or on I64 is an optimizing
compiler. One use of optimization is to perform analysis for uncalled
routines and unreachable paragraphs. The compiler performs the
unreachable code analysis for all levels of optimization, including
/NOOPTIMIZE or the equivalent
-O0
flag. HP COBOL for OpenVMS VAX does not have an /OPTIMIZE qualifier.
B.4.2 Program Listing Differences
Some differences appear in program listings depending upon whether they
were produced by the HP COBOL compiler on OpenVMS Alpha, OpenVMS
I64, OpenVMS VAX, or Tru64 UNIX.
B.4.2.1 Machine Code
With HP COBOL on Alpha and I64, /NOOBJECT and -noobject cause the compiler to suppress code generation, so no machine code is produced either for the listing or for the object module.
If you want the machine code to be included in the program listing, do not use /NOOBJECT or -noobject .
On VAX, /NOOBJECT suppresses just the creation of the .OBJ file. The
compiler still does all the work to generate the object code so it can
be placed in the listing.
B.4.2.2 Module Names
With HP COBOL on Alpha and I64, the name of the first program is
the module name throughout the compilation. On VAX, the module name
changes as the various programs are encountered.
B.4.2.3 COPY and REPLACE Statements
The HP COBOL compiler produces output in slightly different formats on Alpha and I64 and VAX when listing annotations for the COPY statement in COBOL programs.
The following two compiler listing files illustrate the difference in the position of the listing annotations, represented by the letter "L":
HP COBOL on Alpha and I64 Listing File for COPY Statement
1 IDENTIFICATION DIVISION.
2 PROGRAM-ID. DCOP1B.
3 *
4 * This program tests the copy library file.
5 * with a comment in the middle of it.
6 * It should not produce any diagnostics.
7 COPY
8 * this is the comment in the middle
9 LCOP1A.
L 10 ENVIRONMENT DIVISION.
L 11 INPUT-OUTPUT SECTION.
L 12 FILE-CONTROL.
L 13 SELECT FILE-1
L 14 ASSIGN TO "FILE1.TMP".
15 DATA DIVISION.
16 FILE SECTION.
17 FD FILE-1.
18 01 FILE1-REC PIC X.
19 WORKING-STORAGE SECTION.
20 PROCEDURE DIVISION.
21 PE. DISPLAY "***END***"
22 STOP RUN.
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HP COBOL on VAX Listing File for COPY Statement
1 IDENTIFICATION DIVISION.
2 PROGRAM-ID. DCOP1B.
3 *
4 * This program tests the copy library file.
5 * with a comment in the middle of it.
6 * It should not produce any diagnostics.
7 COPY
8 * this is the comment in the middle
9 LCOP1A.
10L ENVIRONMENT DIVISION.
11L INPUT-OUTPUT SECTION.
12L FILE-CONTROL.
13L SELECT FILE-1
14L ASSIGN TO "FILE1.TMP".
15 DATA DIVISION.
16 FILE SECTION.
17 FD FILE-1.
18 01 FILE1-REC PIC X.
19 WORKING-STORAGE SECTION.
20 PROCEDURE DIVISION.
21 PE. DISPLAY "***END***"
22 STOP RUN.
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The HP COBOL compiler also produces output in slightly different formats on Alpha and I64 and VAX when listing a COBOL program with multiple COPY statements on a single line.
The following two compiler listing files illustrate the difference in the position of the listing annotations, represented by the letter "L," for multiple COPY statements on a single line:
HP COBOL on Alpha and I64 Listing File for Multiple COPY Statements
1 IDENTIFICATION DIVISION.
2 PROGRAM-ID. DCOP1J.
3 *
4 * Tests copy with three copy statements on 1 line.
5 *
6 ENVIRONMENT DIVISION.
7 DATA DIVISION.
8 PROCEDURE DIVISION.
9 THE.
10 COPY LCOP1J. COPY LCOP1J. COPY LCOP1J.
L 11 DISPLAY "POIUYTREWQ".
L 12 DISPLAY "POIUYTREWQ".
L 13 DISPLAY "POIUYTREWQ".
14 STOP RUN.
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HP COBOL on VAX Listing File for Multiple COPY Statements
1 IDENTIFICATION DIVISION.
2 PROGRAM-ID. DCOP1J.
3 *
4 * Tests copy with three copy statements on 1 line.
5 *
6 ENVIRONMENT DIVISION.
7 DATA DIVISION.
8 PROCEDURE DIVISION.
9 THE.
10 COPY LCOP1J.
11L DISPLAY "POIUYTREWQ".
12C COPY LCOP1J.
13L DISPLAY "POIUYTREWQ".
14C COPY LCOP1J.
15L DISPLAY "POIUYTREWQ".
16 STOP RUN.
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