jdk10 : simplify jexec build settings

[Baesken, Matthias]

I compared the  jexec.c  versions for  macosx and unix

( jdk/src/java.base/macosx/native/launcher/jexec.c    and    jdk/src/java.base/unix/native/launcher/jexec.c )

And to me it looks like  the  unix version could be used for macosx too  (just in case there is a need to reenable the  build of jexec.c  for macosx one day again).

Comments / suggestions ?

Best regards, Matthias


From: Baesken, Matthias
Sent: Donnerstag, 9. Februar 2017 14:10
To: 'Erik Joelsson' <erik.joelsson at oracle.com>; build-dev at openjdk.java.net; 'core-libs-dev at openjdk.java.net' <core-libs-dev at openjdk.java.net>
Cc: Langer, Christoph <christoph.langer at sap.com>
Subject: RE: jdk10 : simplify jexec build settings

Hello Erik, thanks for the comments .

>>Then there is handling for macosx left , but the build is not enabled for macosx, does it still make sense to include the macosx handling (there is even a separate jexec.c for macosx) :
>
>This is indeed weird. I don't think we ever built jexec for macosx so the source file should likely be removed. That is however a question for core-libs I think.

I include core-libs-dev , can someone comment on  jexec on macosx ?
Currently  jexec.c  is not compiled for macosx (jdk9/10), see  jdk/make/launcher/Launcher-java.base.gmk  .
It is just compiled on linux .

So I wonder -  is it ok to remove  the macosx handling  in the mentioned  makefile   jdk/make/launcher/Launcher-java.base.gmk   for  jexec ?

>This will automatically look in all the directories where source files are supposed to be and pick the most specific one if there are any with the same name.
>Since the share launcher dir contains more src files, you will need to leave the INCLUDE_FILES := jexec.c this time.

>From what I observe in the linux  build log,  just jexec.c  is  compiled into jexec.o and then this single object is used to create the executable ("program")  jexec.
Other src files are not used in the compilation of jexec, so  just using   $(JDK_TOPDIR)/src/$(MODULE)/unix/native/launcher   would be fine (as long as macosx can be dropped).



Best regards, Matthias


From: Erik Joelsson [mailto:erik.joelsson at oracle.com]
Sent: Donnerstag, 9. Februar 2017 13:42
To: Baesken, Matthias <matthias.baesken at sap.com<mailto:matthias.baesken at sap.com>>; build-dev at openjdk.java.net<mailto:build-dev at openjdk.java.net>
Cc: Langer, Christoph <christoph.langer at sap.com<mailto:christoph.langer at sap.com>>
Subject: Re: jdk10 : simplify jexec build settings


Hello,

On 2017-02-09 12:36, Baesken, Matthias wrote:
Hello ,  while adjusting the jspawnhelper build settings with 8174086, it has been noticed that the jexec build settings need some simplification as well.

The bug

https://bugs.openjdk.java.net/browse/JDK-8174242

has been created for this.

When looking into it,  I had some questions :

http://hg.openjdk.java.net/jdk10/jdk10/jdk/file/ae7afa9abe67/make/launcher/Launcher-java.base.gmk

The makefile  (make/launcher/Launcher-java.base.gmk )  handles Solaris 32bit,  but is this really  supported  in jdk 9 or 10  ( I think it was removed in 9 and only 64bit Solaris support remains ) ?
We do not support 32bit Solaris. The issue with jexec for Solaris was raised a while back and the conclusion was to scrap support, so no need to build it for Solaris at all.


ifeq ($(OPENJDK_TARGET_OS), solaris)
  ifeq ($(OPENJDK_TARGET_CPU_BITS), 32)
    BUILD_JEXEC := 1
  endif
endif

ifeq ($(OPENJDK_TARGET_OS), linux)
  BUILD_JEXEC := 1
endif # OPENJDK_TARGET_OS

#
# jdk/make/java/jexec/Makefile
#
ifeq ($(BUILD_JEXEC), 1)

Then there is handling for macosx left , but the build is not enabled for macosx, does it still make sense to include the macosx handling (there is even a separate jexec.c for macosx) :
This is indeed weird. I don't think we ever built jexec for macosx so the source file should likely be removed. That is however a question for core-libs I think.

The makefile logic shouldn't need to be that specific though. Our modern pattern for this is something like this:

SRC := $(call uniq, $(wildcard \
      $(JDK_TOPDIR)/src/$(MODULE)/$(OPENJDK_TARGET_OS)/native/launcher \
      $(JDK_TOPDIR)/src/$(MODULE)/$(OPENJDK_TARGET_OS_TYPE)/native/launcher \
      $(JDK_TOPDIR)/src/$(MODULE)/share/native/launcher))

This will automatically look in all the directories where source files are supposed to be and pick the most specific one if there are any with the same name. Since the share launcher dir contains more src files, you will need to leave the INCLUDE_FILES := jexec.c this time.

For libraries, we have abstracted this construct in the macro FindSrcDirForLib (LibCommon.gmk) but we haven't done the same for launchers yet.

/Erik


  ifeq ($(OPENJDK_TARGET_OS), windows)
  else ifeq ($(OPENJDK_TARGET_OS), macosx)
    BUILD_JEXEC_SRC := $(JDK_TOPDIR)/src/java.base/macosx/native/launcher
  else
    BUILD_JEXEC_SRC := $(JDK_TOPDIR)/src/java.base/unix/native/launcher
  endif

Should I remove  the solaris 32bit / macosx handling  for jexec  from   make/launcher/Launcher-java.base.gmk ?

Regards, Matthias