Hi,

let me chime in to this discussion at this point. So, first of all, Matthias, 
thanks for your work so far.

Erik, I fully understand your points and I agree that it's probably a good idea 
to refactor this whole process of creating these different types of bundles.

Our idea is to provide functionality in the build system to add "public" or 
stripped debug files to the delivery image of the JDK. This would provide 
better information in case of crashes and would hence allow for better 
supportability. That's something we'd probably want to enable in SapMachine 
binary distributions.

So, can we get to add a configure option like the one proposed by Matthias into 
the current code base?
The option should be turned off by default. If it is switched on, the 
images/jdk folder in the build directory will have both, the *stripped.pdb 
files and the standard *.pdb files. However, having *stripped.pdb files around 
should not matter in terms of functionality (for developers and testing) as 
they'd not be used in the presence of the "real" pdb files anyway. The actual 
JDK bundle for delivery would then contain the *stripped.pdb files, renamed to 
*.pdb. And the debug symbols bundle would have the full *.pdb files only. Both 
could then be overlaid as needed.

I think you raised two concerns.
One is that you'd rather like to refactor bundling for several reasons. But I 
guess, should you eventually get to your refactoring, it shouldn't be a problem 
to take the functionality of this new option along.
The other was regarding JMODs. I believe it's correct, that JMODs have never 
carried external debug information. For platforms other than MS Windows that's 
actually not a big problem because debug information can be internalized. And 
jlink has gotten several additions to set flags for stripping that data to the 
right level. I assume if jlinked images on Windows should ever be enabled to 
carry debug information, inclusion of external debug files would have to be 
added to JMODs and jlink. But that's definitely out of scope here.

So, what do you think? What speaks against adding this option (that is off by 
default)?

Thanks
Christoph

> -----Original Message-----
> From: build-dev <build-dev-boun...@openjdk.java.net> On Behalf Of Erik
> Joelsson
> Sent: Donnerstag, 23. Januar 2020 18:49
> To: Baesken, Matthias <matthias.baes...@sap.com>; David Holmes
> <david.hol...@oracle.com>; 'build-dev@openjdk.java.net' <build-
> d...@openjdk.java.net>; 'hotspot-...@openjdk.java.net' <hotspot-
> d...@openjdk.java.net>
> Subject: Re: RFR: 8237192: Generate stripped/public pdbs on Windows for
> jdk images
> 
> 
> On 2020-01-23 00:03, Baesken, Matthias wrote:
> > Hi Erik,  yes true sorry for answering  your comments a bit late .
> >
> >> If a user runs jlink and includes all the jmods we ship with the JDK, the
> result
> >> should be essentially equivalent to the original JDK image. The way the
> >> stripped pdb files are included in the bundles sort of at the last
> >> second of the build here breaks this property.
> > I think we should address this in a separate bug/CR .
> Maybe. I realize that my proposal below is quite a big task. But on the
> other hand, I don't think breaking the relationship between the jmods
> and the distribution bundles is on the table really.
> > Looking for example  into a Linux  build, I see  a lot of debuginfo files  
> > in the
> jdk image (more or less for every shared lib)  .
> > But when looking into the jmods  of that jdk image ,  no debuginfo files are
> in there ( I checked the java.base jmod).
> > So  putting  the  files with debug information into the jmods  seems to be
> something that was not done so far  cross platform  (or is there some build
> switch  for it that I did not check?) .
> > Maybe to keep the jmods as small as possible .
> 
> No, we do not put the debuginfo files in the jmods nor the bundles
> because those are not intended to be shipped to customers. We are
> currently overlaying them into images/jdk in the build output to make
> them available for local debugging. (This is convoluted and I would very
> much like to get away from this practice at some point so that there is
> a 1-1 mapping between images/jdk and bundles/jdk*-bin.tar.gz.) The
> stripped pdb files you are proposing are on the contrary intended for
> shipping to customers (as I understand your proposal) so comparing them
> with the debuginfo files is not relevant.
> 
> Now if MS had been kind enough to define a separate file type for the
> stripped pdbs, so that they could live alongside the full pdbs, we
> wouldn't have this issue. The heart of the problem is that only one set
> of files (either stripped or full) can be present and usable in
> images/jdk at a time. We have 2 main uses for images/jdk.
> 
> 1. Developer running and debugging locally
> 
> 2. Serve as the source for generating the distribution bundles
> 
> We currently have one image serving both of these purposes, which is
> already creating complicated and convoluted build steps. To properly
> solve this I would argue for splitting these two apart into two
> different images for the two different purposes. The build procedure
> would then be, first build the images for distribution, only containing
> what should go into each bundle. Then create the developer jdk image by
> copying files from the distribution images. On Windows, the first image
> would contain the stripped pdbs and when building the second, those
> would get overwritten with the full pdbs.
> 
> Now that I figured out a working model that would solve a bunch of other
> problems as well, I would love to implement it, but I doubt I will have
> time in the near future.
> 
> /Erik
> 
> >
> >> To properly implement this, care will need to be taken to juggle the two
> >> sets of pdb files around, making sure each build and test use case has
> >> the correct one in place where and when it's needed. Quite possibly, we
> >> cannot cover all use cases with one build configuration. Developers
> >> needing the full debug symbols when debugging locally would likely need
> >> to disable the stripped symbols so they get the full symbols everywhere.
> >> Possibly this would need to be the default for debug builds and
> >> configurable for release builds.
> >  From my limited experience , the developers  do not work with the
> bundles (that  would contain now after my patch the stripped pds)  but with
> a "normal" jdk image that  is created my make all.
> >
> > Best regards, Matthias
> >
> >
> >
> >> This still does not address anything in my objection.
> >>
> >> /Erik
> >>
> >> On 2020-01-22 07:46, Baesken, Matthias wrote:
> >>> Hello,  here is an updated version  :
> >>>
> >>> http://cr.openjdk.java.net/~mbaesken/webrevs/8237192.3/
> >>>
> >>> this one supports a configure switch  "--enable-stripped-pdbs"    to
> enable
> >> the feature .
> >>> Best regards, Matthias
> >>>
> >>>
> >>>> -----Original Message-----
> >>>> From: Baesken, Matthias
> >>>> Sent: Dienstag, 21. Januar 2020 11:03
> >>>> To: 'David Holmes' <david.hol...@oracle.com>; 'build-
> >>>> d...@openjdk.java.net' <build-dev@openjdk.java.net>; 'hotspot-
> >>>> d...@openjdk.java.net' <hotspot-...@openjdk.java.net>
> >>>> Subject: RE: RFR: 8237192: Generate stripped/public pdbs on Windows
> for
> >>>> jdk images
> >>>>
> >>>>
> >>>> Hi David ,  yes I think it makes sense to have a configure option for 
> >>>> this .
> >>>> Not everyone would like to have a larger JDK (even it is only a bit
> larger).
> >>>>

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