Hi Ichiroh, your proposal seems to make sense. I have created a bug for this: https://bugs.openjdk.java.net/browse/JDK-8204541 Can you please generate a webrev (referencing this bug, -c option of webrev.ksh) and mail it over to me. Then I'll upload it and you can post an official RFR mail. Best regards Christoph

-----Original Message----- From: Ichiroh Takiguchi [mailto:takiguc@linux.vnet.ibm.com] Sent: Dienstag, 5. Juni 2018 08:59 To: Baesken, Matthias <matthias.baesken@sap.com> Cc: Langer, Christoph <christoph.langer@sap.com>; 'build- dev@openjdk.java.net' <build-dev@openjdk.java.net>; ppc-aix-port- dev@openjdk.java.net; core-libs-dev@openjdk.java.net; Lindenmaier, Goetz <goetz.lindenmaier@sap.com> Subject: RE: RFR : 8202322: AIX: symbol visibility flags not support on xlc 12.1

Hello Matthias and Christoph. Thank you for your explanations.

I did not have enough knowledge about "visibility".

I created following patches.

================================ diff -r 02934b0d661b src/java.base/share/native/libjimage/NativeImageBuffer.cpp --- a/src/java.base/share/native/libjimage/NativeImageBuffer.cpp Wed May 30 14:46:28 2018 +0200 +++ b/src/java.base/share/native/libjimage/NativeImageBuffer.cpp Tue Jun 05 12:10:41 2018 +0900 @@ -39,7 +39,9 @@ #include "imageFile.hpp" #include "inttypes.hpp" #include "jimage.hpp" +#if !defined(_AIX) #include "osSupport.hpp" +#endif

#include "jdk_internal_jimage_NativeImageBuffer.h"

diff -r 02934b0d661b src/java.base/unix/native/include/jni_md.h --- a/src/java.base/unix/native/include/jni_md.h Wed May 30 14:46:28 2018 +0200 +++ b/src/java.base/unix/native/include/jni_md.h Tue Jun 05 12:10:41 2018 +0900 @@ -29,7 +29,8 @@ #ifndef __has_attribute #define __has_attribute(x) 0 #endif -#if (defined(__GNUC__) && ((__GNUC__ > 4) || (__GNUC__ == 4) && (__GNUC_MINOR__ > 2))) || __has_attribute(visibility) +#if (defined(__GNUC__) && ((__GNUC__ > 4) || (__GNUC__ == 4) && (__GNUC_MINOR__ > 2))) || __has_attribute(visibility) \ + || (defined(_AIX) && (defined(__xlC__) && (__xlC__ >= 0xD01))) #ifdef ARM #define JNIEXPORT __attribute__((externally_visible,visibility("default"))) #define JNIIMPORT __attribute__((externally_visible,visibility("default"))) ================================

If "osSupport.hpp" was included, XLC++ compiler complained. I could not understand, which part was invalid... I'm not sure, "osSupport.hpp" is really required on NativeImageBuffer.cpp or not...

I added __xlC__ macro to determine XLC/C++'s version# into jni_md.h. [1] 0xD01 means 13.1 by hexadecimal.

I checked symbol table by "dump -Tv -X64". [2] It seemed it was fine, some symbols were hidden.

Does someone review my code?

[1] https://www.ibm.com/support/knowledgecenter/en/SSGH2K_13.1.3/com.i bm.xlc1313.aix.doc/compiler_ref/xlmacros.html [2] https://www.ibm.com/developerworks/aix/library/au-aix-symbol- visibility/index.html

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Hi , my change 8202322 just handled the fact that the visibility - flags are not supported with xlc 12.1 , so setting them generated a TON of compile - time warnings .

The introduction of the "-qvisibility=hidden" came with the mapfile removal changes :

8200358: Remove mapfiles for JDK executables http://hg.openjdk.java.net/jdk/jdk/rev/210cf224b690

8200178: Remove mapfiles for JDK native libraries http://hg.openjdk.java.net/jdk/jdk/rev/396ea30afbd5

I guess it might need further testing+adjustments to make the "visibility hiding" work nicely with XLC13 , but currently we build only with XLC12 .

As a workaround you might want to remove the "-qvisibility=hidden" setting for XLC 13 as well , like I did for XLC12 with the change 8202322 .

Best regards, Matthias

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-----Original Message----- From: Langer, Christoph Sent: Freitag, 1. Juni 2018 10:57 To: Ichiroh Takiguchi <takiguc@linux.vnet.ibm.com> Cc: Baesken, Matthias <matthias.baesken@sap.com>; 'build- dev@openjdk.java.net' <build-dev@openjdk.java.net>; ppc-aix-port- dev@openjdk.java.net; core-libs-dev@openjdk.java.net; Lindenmaier, Goetz <goetz.lindenmaier@sap.com> Subject: RE: RFR : 8202322: AIX: symbol visibility flags not support on xlc 12.1

Hi Ichiroh,

we do not use the XLC 13 compiler on AIX yet here at SAP and I believe nobody of my colleagues has played with it yet. So you are on a new playground here 😊

However, I believe the idea in OpenJDK with the abolition of map files is that symbols should be invisible externally unless they are declared exported, e.g. JNIEXPORT. So I would think "-qvisibility=hidden" should be the correct default and whatever JNIEXPORT expands to should contain the right attributes to get that symbol visible.

Can you check if either my assumption is completely wrong, JNIEXPORT does not expand to the right thing, XLC 13 has a bug or maybe just sume specific required symbols are not declared correctly?

Best regards Christoph

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-----Original Message----- From: Ichiroh Takiguchi [mailto:takiguc@linux.vnet.ibm.com] Sent: Donnerstag, 31. Mai 2018 09:55 To: Langer, Christoph <christoph.langer@sap.com> Cc: Baesken, Matthias <matthias.baesken@sap.com>; 'build- dev@openjdk.java.net' <build-dev@openjdk.java.net>; ppc-aix-port- dev@openjdk.java.net; core-libs-dev@openjdk.java.net; Lindenmaier, Goetz <goetz.lindenmaier@sap.com> Subject: RE: RFR : 8202322: AIX: symbol visibility flags not support on xlc 12.1

Hello. 8202322 was integrated into jdk-11+15. I'm using XLC 13.1.3 on AIX 7.1.4. Build was failed because of "-qvisibility=hidden" on make/lib/LibCommon.gmk. According to "XL C/C++ for AIX 13.1.3" documentation [1], "-qvisibility=hidden" cannot create shared libraries entry points. For example, libverify.so was there, but entry points were not resolved by "-lverify" option. I think it should be "-qvisibility=default" (I tried, it worked) or "-qvisibility=protected" (I had not tried) ? I'm not familiar with -qvisibility option, but I'd like to find out right way.

[1]

https://www.ibm.com/support/knowledgecenter/SSGH3R_13.1.3/com.ibm.

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xlcpp1313.aix.doc/compiler_ref/opt_visibility.html

On 2018-05-16 16:08, Langer, Christoph wrote:

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Hi Matthias,

yes, reviewed.

Best regards Christoph

From: Baesken, Matthias Sent: Mittwoch, 16. Mai 2018 09:06 To: Langer, Christoph <christoph.langer@sap.com>; 'build-dev@openjdk.java.net' <build-dev@openjdk.java.net>; ppc-aix-port-dev@openjdk.java.net; core-libs-dev@openjdk.java.net Cc: Lindenmaier, Goetz <goetz.lindenmaier@sap.com> Subject: RE: RFR : 8202322: AIX: symbol visibility flags not support on xlc 12.1

Hi Christoph can I add you as second reviewer (other reviewer was Erik Joelsson) can push the change ?

Best regards, Matthias

From: Langer, Christoph Sent: Donnerstag, 26. April 2018 16:38 To: Baesken, Matthias <matthias.baesken@sap.com<mailto:matthias.baesken@sap.com>>; 'build-dev@openjdk.java.net' <build-dev@openjdk.java.net<mailto:build- dev@openjdk.java.net>>; ppc-aix-port-dev@openjdk.java.net<mailto:ppc-aix-port- dev@openjdk.java.net>; core-libs-dev@openjdk.java.net<mailto:core-libs- dev@openjdk.java.net> Cc: Simonis, Volker <volker.simonis@sap.com<mailto:volker.simonis@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)

On 2018-06-01 21:12, Baesken, Matthias wrote: -

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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@openjdk.java.net' <build-dev@openjdk.java.net<mailto:build- dev@openjdk.java.net>>; ppc-aix-port-dev@openjdk.java.net<mailto:ppc-aix-port- dev@openjdk.java.net>; core-libs-dev@openjdk.java.net<mailto:core-libs- dev@openjdk.java.net> Cc: Langer, Christoph <christoph.langer@sap.com<mailto:christoph.langer@sap.com>>; Simonis, Volker <volker.simonis@sap.com<mailto:volker.simonis@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