postgres/doc/FAQ_AIX

From: Zeugswetter Andreas <ZeugswetterA@spardat.at>
$Date: 2005/12/08 21:36:50 $

On AIX 4.3.2 PostgreSQL compiled with the native IBM compiler xlc
(vac.C 5.0.1) passes all regression tests.  Other versions of OS and
compiler should also work. If you don't have a powerpc or use gcc you
might see rounding differences in the geometry regression test.

Use the following configure flags in addition to your own
if you have readline or libz there:
--with-includes=/usr/local/include --with-libraries=/usr/local/lib

There will probably be warnings about 0.0/0.0 division and duplicate
symbols which you can safely ignore.

Compiling PostgreSQL with gcc (2.95.3) on AIX also works.

You need libm.a that is in the fileset bos.adt.libm.  (Try the
following command.)
$ lslpp -l bos.adt.libm


---
From: Christopher Browne <cbbrowne@ca.afilias.info>
Date: 2005-07-15

On AIX 5.3, there have been some problems getting PostgreSQL to
compile and run using GCC.

1.  You will want to use a version of GCC subsequent to 3.3.2,
    particularly if you use a prepackaged version.  We had good
    success with 4.0.1.

    Problems with earlier versions seem to have more to do with the
    way IBM packaged GCC than with actual issues with GCC, so that if
    you compile GCC yourself, you might well have success with an
    earlier version of GCC.

2.  AIX 5.3 has a problem where sockadr_storage is not defined to be
    large enough.  In version 5.3, IBM increased the size of
    sockaddr_un, the address structure for UNIX Domain Sockets, but
    did not correspondingly increase the size of sockadr_storage.

    The result of this is that attempts to use UDS with PostgreSQL
    lead to libpq overflowing the data structure.  TCP/IP connections
    work OK, but not UDS, which prevents the regression tests from
    working.

   The nonconformance may be readily demonstrated by compiling and
   running the following C program which calculates and compares the
   sizes of the various structures:

test_size.c
------------

---------- snip here - test_size.c ----------------------------
#include <stdio.h>
#include <sys/un.h>
#include <sys/socket.h>
int main (int argc, char *argv[]) {
        struct sockaddr_storage a;
        struct sockaddr_un b;
        printf("Size of sockadr_storage: %d\n", sizeof(a));
        printf ("Size of sockaddr_un:%d\n", sizeof(b));

        if (sizeof(a) >= sizeof(b)) 
                printf ("Conformant to RFC 3493\n");
        else
                printf ("Non-conformant to RFC 3493\n");
} 
---------- snip here - test_size.c ----------------------------


The problem was reported to IBM, and is recorded as bug report
PMR29657.

An immediate resolution is to alter _SS_MAXSIZE to = 1025 in
/usr/include/sys/socket.h, which will resolve the immediate problem.

It appears that the "final" resolution will be to alter _SS_MAXSIZE to
1280, making the size nicely align with page boundaries.

IBM will be providing a fix in the next maintenance release (expected
in October 2005) with an updated socket.h.
---
PMR29657 was resolved in APAR IY74147: INCOMPATIBILITY BETWEEN
SOCKADDR_UN AND SOCKADDR_STORAGE STRUCT

APAR information
APAR number	IY74147
Reported component name	AIX 5.3
Reported component ID	5765G0300
Reported release	530
Status	CLOSED PER
PE	NoPE
HIPER	NoHIPER
Submitted date	2005-07-18
Closed date	2005-07-18
Last modified date	2005-09-06

If you upgrade to maintenance level 5300-03, that will include this
fix.  Use the command "oslevel -r" to determine what maintenance level
you are at.
---
From: Christopher Browne <cbbrowne@ca.afilias.info>
Date: 2005-07-15

Some of the AIX tools may be "a little different" from what you may be
accustomed to on other platforms.  If you are looking for a version of
ldd, useful for determining what object code depends on what
libraries, the following URLs may help you...

http://www.faqs.org/faqs/aix-faq/part4/section-22.html

http://www.han.de/~jum/aix/ldd.c
---

AIX, readline, and postgres 8.1.x:
----------------------------------

If make check doesn't work on AIX with initdb going into an infinite
loop or failing with child processes terminated with signal 11, the 
problem could be the installed copy of readline.  Previously a patch to 
dynahash.c was suggested to get around this, don't use it, better ways
to get postgres working exist.

See <http://archives.postgresql.org/pgsql-patches/2005-11/msg00139.php>
for details about the problem.

Working around the problem:
---------------------------
1) Use the new 8.2devel backend Makefile:
After the matter of readline's export list and the problems that were
occurring on AIX because of it being linked to the backend, a filter
to exclude unneeded libraries from being linked against the backend was
added.  Get revision 1.112 of src/backend/Makefile from CVS and replace
the copy that came with postgres with it.  Build normally.

2) Use libedit:
There are a few libedit ports available online.  Build and install the
desired port.  If libreadline.a can be found in /lib, /usr/lib, or in
any location passed to postgres' configure via "--with-libraries=",
readline will be detected and used by postgres.  IBM's rpm of readline
creates a symlink to /opt/freeware/lib/libreadline.a in /lib, so merely 
excluding /opt/freeware/lib from the passed library path does not stop
readline from being used.  

If the linker cannot avoid finding libreadline.a, use revision 1.433 
configure.in and 1.19 config/programs.m4 from CVS, change 8.2devel to 
the appropriate 8.1.x in configure.in and run autoconf.  Add the 
configure flag "--with-libedit-preferred".

If the version of libedit used calls its "history.h" something other
than history.h, place a symlink called history.h to it somewhere that
the C preprocessor will check.

3) Configure with "--without-readline":
postgres can be configured with the option "--without-readline".  When
this is enabled, postgres will not link against libreadline or libedit.
psql will not have history, tab completion, or any of the other niceties
that readline and libedit bring, but external readline wrappers exist
that add that functionality.

4) Use readline 5.0:
Readline 5.0 does not induce the problems, however it does export
memcpy and strncpy when built using the easy method of "-bexpall".  Like
4.3, it is possible to do a build that does not export these symbols,
but it does take considerable manual effort and the creation of export
files.

References
----------
"AIX 5L Porting Guide"
  IBM Redbook
  http://www.redbooks.ibm.com/redbooks/pdfs/sg246034.pdf
  http://www.redbooks.ibm.com/abstracts/sg246034.html?Open
  
"Developing and Porting C and C++ Applications on AIX"
  IBM Redbook
  http://www.redbooks.ibm.com/redbooks/pdfs/sg245674.pdf
  http://www.redbooks.ibm.com/abstracts/sg245674.html?Open