RFR : 8202322: AIX: symbol visibility flags not support on xlc 12.1

[Thomas Stüfe]

Hi,

This was added by "8200178: Remove mapfiles for JDK native libraries".
But if the flag is not accepted, what is the default behavior? Do we
now export everything?

I'd like to understand this first before removing the flag to get rid
of the warnings.

Best Regards, Thomas

On Thu, Apr 26, 2018 at 5:16 PM, Volker Simonis
<volker.simonis at gmail.com> wrote:
> Hi Matthias,
>
> after Bhaktavatsal Reddy's report about the problems with
> "-qvisibility" with xlC 13 and taking into account that we can't test
> this anyway because we don't currently have xlC 13
>  on our machines I think it would be best to completely remove this
> option for now on AIX. Once we get xlC 13 we can revisit the issue.
>
> Thanks,
> Volker
>
>
> On Thu, Apr 26, 2018 at 4:59 PM, Bhaktavatsal R Maram
> <bhamaram at in.ibm.com> wrote:
>> Hi Matthias,
>>
>> At this point, I think we can remove the flag as you found that it is not supported in XLC < 13. And with XLC 13, it require more work to use this flag.
>>
>> Thanks,
>> Bhaktavatsal Reddy
>>
>>
>>
>> -----"Baesken, Matthias" <matthias.baesken at sap.com> wrote: -----
>> To: "Langer, Christoph" <christoph.langer at sap.com>, "'build-dev at openjdk.java.net'" <build-dev at openjdk.java.net>, "ppc-aix-port-dev at openjdk.java.net" <ppc-aix-port-dev at openjdk.java.net>, "core-libs-dev at openjdk.java.net" <core-libs-dev at openjdk.java.net>
>> From: "Baesken, Matthias" <matthias.baesken at sap.com>
>> Date: 04/26/2018 08:23PM
>> Cc: "Simonis, Volker" <volker.simonis at sap.com>, Bhaktavatsal R Maram    <bhamaram at in.ibm.com>
>> Subject: RE: RFR : 8202322: AIX: symbol visibility flags not support on xlc 12.1
>>
>>
>>  Hello Christoph,   I think  all XLC versions  < 12.1   are unsupported  (and probably not working anyway)  for the OpenJDK  build .
>>  I am only aware   of  XLC  versions  12.1  and 13.1    which  work / in case of 13.1  “might” work   for OpenJDK compilation .
>>  And for 12.1  I want to remove the flags  .
>>
>>  ( waiting for the feedback  of   Bhaktavatsal Reddy ,  in case he  prefers it  I remove them for all xlC versions including 13.1 )
>>
>>  Best regards, Matthias
>>
>>
>>
>>
>>
>>
>>  From: Langer, Christoph
>>  Sent: Donnerstag, 26. April 2018 16:38
>>  To: Baesken, Matthias <matthias.baesken at sap.com>; 'build-dev at openjdk.java.net' <build-dev at openjdk.java.net>; ppc-aix-port-dev at openjdk.java.net; core-libs-dev at openjdk.java.net
>>  Cc: Simonis, Volker <volker.simonis at sap.com>
>>  Subject: RE: RFR : 8202322: AIX: symbol visibility flags not support on xlc 12.1
>>
>>  Hi Matthias,
>>
>>  to me the change in principal looks good.
>>
>>  I’m wondering if it is possible to do a comparison like xlc < 13 (e.g. extract major number before the first dot, then compare numerically) – but maybe it is too complicated and the current single version compare suits  our needs ?
>>
>>  Best regards
>>  Christoph
>>
>>
>>
>>
>>  From: Baesken, Matthias
>>  Sent: Donnerstag, 26. April 2018 16:14
>>  To: 'build-dev at openjdk.java.net' <build-dev at openjdk.java.net>; ppc-aix-port-dev at openjdk.java.net; core-libs-dev at openjdk.java.net
>>  Cc: Langer, Christoph <christoph.langer at sap.com>; Simonis, Volker <volker.simonis at sap.com>
>>  Subject: RFR : 8202322: AIX: symbol visibility flags not support on xlc 12.1
>>
>>  Hello  ,  could you please review this small adjustment to  the symbol visibility compilation settings on AIX ?
>>  Currently  we use  XLC 12.1  to compile  JDK on AIX .
>>
>>  However XLC 12.1   does not support  the “-qvisibility=hidden”  setting currently set on AIX.
>>  It was introduced with  XLC 13.1 . Christoph found some info about it here :
>>
>>  https://www.ibm.com/developerworks/aix/library/au-aix-symbol-visibility-part2/index.html
>>
>>  Setting it  only generates  hundreds  of warnings  in the build log , warnings look like this :
>>  XlC12.1
>>
>>  bash-4.4$ xlC -qversion
>>  IBM XL C/C++ for AIX, V12.1 (5765-J02, 5725-C72)
>>  Version: 12.01.0000.0019
>>
>>  bash-4.4$ xlC -qvisibility=hidden sizeof.c -o sizeof_aixxlc
>>  1506-173 (W) Option visibility=hidden is not valid. Enter xlC for list of valid options.
>>
>>  Compare to XLC13.1
>>
>>  bash-3.00$ xlC -qversion
>>  IBM XL C/C++ for AIX, V13.1 (5725-C72, 5765-J07)
>>  Version: 13.01.0000.0008
>>  bash-3.00$ xlC -qvisibility=default sizeof.c -o sizeof_aixxlc
>>  bash-3.00$ xlC -qvisibility=hidden sizeof.c -o sizeof_aixxlc
>>
>>
>>  So it is better to avoid  setting these flags when using xlc12.1   .
>>  Please review :
>>
>>  Bug :
>>
>>  https://bugs.openjdk.java.net/browse/JDK-8202322
>>
>>  Change :
>>
>>  http://cr.openjdk.java.net/~mbaesken/webrevs/8202322/
>>
>>
>>  Best regards, Matthias
>>
>>
>>
>>