[DEC C] %LINK-I-UDFSYM, SYS_ERRLIST %LINK-I-UDFSYM, SYS_NERR
COPYRIGHT (c) 1988, 1993 by Digital Equipment Corporation.
ALL RIGHTS RESERVED. No distribution except as provided under contract.
Copyright (c) Digital Equipment Corporation 1995, 1996. All rights reserved.
PRODUCT: DEC C for OpenVMS Alpha, Versions 4.0 and below
OP/SYS: OpenVMS Alpha, Version 6.2
COMPONENT: STARLET
SOURCE: Digital Equipment Corporation
SYMPTOM:
Re-linking some C objects after upgrading to OpenVMS Alpha V6.2, results
in linker warnings similar to the following:
%LINK-W-NUDFSYMS, 2 undefined symbols:
%LINK-I-UDFSYM, SYS_ERRLIST
%LINK-I-UDFSYM, SYS_NERR
%LINK-W-USEUNDEF, undefined symbol SYS_NERR referenced
in psect $LINK$ offset %X000000A0
in SNLER FOO file device:[directory]filename.type;version
%LINK-W-USEUNDEF, undefined symbol SYS_ERRLIST referenced
in psect $LINK$ offset %X000000A8
in module SNLER file device:[directory]filename.type;version
DIGITAL RESPONSE:
Engineering has acknowledged this problem and plans to address it in a
future release.
WORKAROUND 1:
The ECO kit ALPACRT may address the problem described in this article.
Refer to the ECO-SUMMARY article to determine if this ECO corrects the
problem for your specific configuration. More information regarding
this kit may be found in the ECO-SUMMARY database by using a query of
ALPACRT.
***Note: If you have *already* used the workaround described in this
article *and* plan to install the ALPACRT ECO, you MUST
*first* remove the global symbols SYS_ERRLIST and SYS_NERR.
Use the following command to do this:
$ LIBRARY/DELETE=DECC$SYS_ERRLIST SYS$LIBRARY:STARLET.OLB
If you do not perform the above step, the installation of
ALPACRT will fail. Note that the installation of this
ECO fails, ONLY FOR THOSE CUSTOMERS who utilized this
article. If you have applied this workaround, you will
see the following error when installing the ALPACRT
patch:
%LIBRAR-E-DUPGLOBAL, global symbol SYS_NERR from file CRT.OBJ;1
already in library STARLET.OLB;1
With ALPACRT, these global symbols are included in the
CRTL.OBJ object file that is replaced into STARTLET.OLB.
When this occurs, you will get a DUPGLOBALS error. That is,
the global symbols SYS_ERRLIST and SYS_NERR are now defined
twice (hence DUPlicates).
WORKAROUND 2:
Use one of the following workarounds:
o If possible, recompile the module using Version 4.1 or later of
DEC C for OpenVMS ALPHA.
o Modify your link to include SYS$LIBRARY:DECC$SYS_ERRLIST.OBJ.
o Insert DECC$SYS_ERRLIST.OBJ into SYS$LIBRARY:STARLET.OLB.
This article includes the source code in both C and MACRO to build
DECC$SYS_ERRLIST.OBJ. Once this module is built it should be placed
into SYS$LIBRARY and may be inserted into SYS$LIBRARY:STARLET.OLB,
if you wish.
ANALYSIS:
Prior to OpenVMS Alpha V6.2 the symbols SYS_NERR and SYS_ERRLIST were
available in SYS$LIBRARY:STARLET.OLB. DEC C RTL entries in starlet
should be prefixed by DECC$. Since this was not the case for SYS_NERR
and SYS_ERRLIST, they were causing "name pollution" in STARLET and were
removed in OpenVMS ALPHA V6.2.
Compiling with DEC C V4.1 or later on OpenVMS ALPHA V6.2 systems will
generate references to DECC$GL_SYS_NERR and DECC$GA_SYS_ERRLIST which
will be resolved via the DEC C RTL. Compiling with a version of DEC C
prior to V4.1 on OpenVMS Alpha V6.2 systems will not generate the
prefixed references. This will cause the link to fail.
If you cannot recompile your programs on OpenVMS ALPHA V6.2 with DEC C
V4.1 or later, engineering has provided a workaround which consists of a
source program (which can be written in either C or MACRO called
DECC$SYS_ERRLIST.C or DECC$SYS_ERRLIST.MAR respectively) and a command
file (DECC$SYS_ERRLIST.COM).
The source program (DECC$SYS_ERRLIST.C or DECC$SYS_ERRLIST.MAR) is used
to resolve references to SYS_NERR and SYS_ERRLIST. The source needs to
be either compiled or assembled (depending on your choice of language)
into DECC$SYS_ERRLIST.OBJ and then moved to SYS$LIBRARY.
DECC$SYS_ERRLIST.COM is provided to insert DECC$SYS_ERRLIST.OBJ back
into STARLET if you chose to do this. It will cause name pollution,
which may not be an issue for your environment. DECC$SYS_ERRLIST.COM
should be moved to SYS$LIBRARY.
The sources for DECC$SYS_ERRLIST.C, DECC$SYS_ERRLIST.MAR,
DECC$SYS_ERRLIST.COM are listed here along with the steps for using
them.
1. Create either DECC$SYS_ERRLIST.C or DECC$SYS_ERRLIST.MAR.
Note:
It is not necessary to have the DEC C compiler installed
on your system to be able to link or run DEC C programs.
For sites that do not have the DEC C compiler, use the MACRO
code in step 1.B to resolve these undefined symbols.
1.A Creating DECC$SYS_ERRLIST.C
$ create DECC$SYS_ERRLIST.C
# pragma extern_model save
# pragma extern_model relaxed_refdef
char *sys_errlist[] = {"",0};
int sys_nerr = 0;
# pragma extern_model restore
Compile DECC$SYS_ERRLIST.C.
$ cc DECC$SYS_ERRLIST
1.B Creating DECC$SYS_ERRLIST.MAR
$ create DECC$SYS_ERRLIST.MAR
.TITLE DECC$SYS_ERRLIST "DECC$SYS_ERRLIST"
.PSECT $LITERAL$, PIC, CON, REL, LCL, SHR, NOEXE, RD, NOWRT
ZERO:
.ASCII <0>
.PSECT SYS_ERRLIST, NOPIC, OVR, REL, GBL,NOSHR, NOEXE, RD, WRT
SYS_ERRLIST::
.ADDRESS ZERO
.long 0
.PSECT SYS_NERR, NOPIC, OVR, REL, GBL,NOSHR, NOEXE, RD, WRT
SYS_NERR::
.LONG 0
.end
Assemble the MACRO code.
$MACRO decc$sys_errlist
2. Move DECC$SYS_ERRLIST.OBJ to SYS$LIBRARY
3. Create DECC$SYS_ERRLIST.COM
$!
$! Copyright 1995 by Digital Equipment Corporation. All rights reserved.
$!
$! DECC$SYS_ERRLIST.COM
$!
$! This command procedure inserts the module SYS$LIBRARY:DECC$SYS_ERRLIST.OBJ
$! into the SYS$LIBRARY:STARLET.OLB object library. This module defines two
$! symbols named SYS_ERRLIST and SYS_NERR which may be needed to resolve
$! undefined symbols in your LINK command.
$!
$! If a LINK command results in one or both of these symbols being undefined,
$! then we recommend that you take one of the following corrective actions:
$!
$! o Recompile the module using DEC C for OpenVMS ALPHA V4.1 or later, or
$! o Modify your link to include SYS$LIBRARY:DECC$SYS_ERRLIST.OBJ, or
$! o Have the system manager invoke this command procedure
$!
$! Invoking this command procedure will make these two symbols automatically
$! available to the LINKER via STARLET.
$!
$! These symbols were removed from STARLET beginning in OpenVMS Alpha V6.2.
$! Only symbols prefixed with the facility specific prefix should be found
$! in STARLET. This avoids the possibility of two separate facilities
$! defining the same symbol.
$!
$! The reason we are supplying this object file and command procedure is
$! that versions of the DEC C compiler prior running on pre-OpenVMS ALPHA V6.2
$! systems could generate references to these unprefixed symbols. SYS_NERR
$! and SYS_ERRLIST will be prefixed as of OpenVMS V6.2.
$!
$
$ LIBRARY/INSERT SYS$LIBRARY:STARLET.OLB SYS$LIBRARY:DECC$SYS_ERRLIST.OBJ
$
4. Move DECC$SYS_ERRLIST.COM to SYS$LIBRARY
5. To resolve references to SYS_NERR or SYS_ERRLIST link with SYS$LIBRARY:
DECC$SYS_ERRLIST.OBJ directly. Or invoke SYS$LIBRARY:DECC$SYS_ERRLIST.COM
to insert this object module into SYS$LIBRARY:STARLET.OLB
