[OpenJDK 2D-Dev] RFR(xxxs): 8200052: libjavajpeg: Fix compile warning in jchuff.c

Phil Race philip.race at oracle.com
Thu May 31 17:33:46 UTC 2018 

I've grabbed the bug from Thomas and re-opened it

https://bugs.openjdk.java.net/browse/

Your webrev was stripped so I've uploaded here :

http://cr.openjdk.java.net/~prr/8200052/

It looks fine to me but I am a bit hazy about who to give attribution 
for the fix ..
It is small enough to not require an OCA so there's no issue there if we 
attribute
it to the IJG guy.

-phil.

On 05/31/2018 06:31 AM, Adam Farley8 wrote:
> An attachment in the email has been found to contain executable code 
> and has been removed.
>
> File removed : webrev.zip, zip,html,js
> ------------------------------------------------------------------------
> Hi Phil,
>
> As requested:
>
>
>
> FYI: I've also contacted Guido, confirmed that the fix worked, and asked
> him to go ahead with merging the fix into his code base.
>
> Best Regards
>
> Adam Farley
>
>
> Phil Race <philip.race at oracle.com> wrote on 30/05/2018 18:06:19:
>
> > From: Phil Race <philip.race at oracle.com>
> > To: Adam Farley8 <adam.farley at uk.ibm.com>
> > Cc: 2d-dev <2d-dev at openjdk.java.net>, Andrew Leonard
> > <andrew_m_leonard at uk.ibm.com>, build-dev <build-
> > dev at openjdk.java.net>, Magnus Ihse Bursie
> > <magnus.ihse.bursie at oracle.com>, "Thomas Stüfe" 
> <thomas.stuefe at gmail.com>
> > Date: 30/05/2018 18:07
> > Subject: Re: [OpenJDK 2D-Dev] RFR(xxxs): 8200052: libjavajpeg: Fix
> > compile warning in jchuff.c
> > 
> > Thank you for persevering with this. Please submit a webrev with this
> > change .. I think you can leave out the change to jerror.h in the 
> jpeg6b case.
> >
> > -phil.
>
> > On 05/30/2018 09:08 AM, Adam Farley8 wrote:
> > Hi Phil, 
> >
> > I spoke with the jpegclub rep "Guido", and he was very helpful.
> >
> > He agreed to accept a code change, but recommended an error instead
> > of a while check.
> >
> > ------------------------------ Line 808:
> > <       while (bits[j] == 0)
> > <         j--;
> > ---
> > >       while (bits[j] == 0) {
> > >         if (j == 0)
> > >           ERREXIT(cinfo, JERR_HUFF_CLEN_OVERFLOW);
> > >         j--;
> > >       }
> > ------------------------------
> >
> > This makes sense to me, and I verified that it prevents the error.
> >
> > He says:
> > @@@@@@@@@@@@
> > For the release version I would replace the specific
> > JERR_HUFF_CLEN_OVERFLOW by the more general
> > JERR_HUFF_CLEN_OUTOFBOUNDS so that it suits both cases, this
> > requires a change in jerror.h:
> >
> > -JMESSAGE(JERR_HUFF_CLEN_OVERFLOW, "Huffman code size table overflow")
> > +JMESSAGE(JERR_HUFF_CLEN_OUTOFBOUNDS, "Huffman code size table out 
> of bounds")
> >
> > The next version (9d) is planned for release in January 2020.
> > A pre-release package will be provided in 2019 on http://
> > jpegclub.org/reference/reference-sources/, I will send you a 
> notification.
> > @@@@@@@@@@@@
> >
> > While we *could* make the jerror.h change, I suggest we don't for
> > now. If we merge from upstream in January 2020, we'll get that
> > change anyway when the time comes.
> >
> > So what do you say to including the dashed change referenced above
> > to fix our problem now, safe in the knowledge that upstream will be
> > similarly modified (except with the new error type).
> >
> > Best Regards
> >
> > Adam Farley
> >
> > P.S. I'm holding off on giving Guido the green light until after
> > people say if they're happy with the error-enabled version of the fix.
> >
> > Adam Farley8/UK/IBM wrote on 14/05/2018 11:06:28:
> >
> > > From: Adam Farley8/UK/IBM
> > > To: Phil Race <philip.race at oracle.com>
> > > Cc: 2d-dev <2d-dev at openjdk.java.net>, Andrew Leonard
> > > <andrew_m_leonard at uk.ibm.com>, build-dev <build-
> > > dev at openjdk.java.net>, Magnus Ihse Bursie
> > > <magnus.ihse.bursie at oracle.com>, "Thomas Stüfe" 
> <thomas.stuefe at gmail.com>
> > > Date: 14/05/2018 11:06
> > > Subject: Re: [OpenJDK 2D-Dev] RFR(xxxs): 8200052: libjavajpeg: Fix
> > > compile warning in jchuff.c
> > >
> > > Hi Phil,
> > >
> > > Would an acceptable compromise be to deliver the source code change
> > > and send the code to the upstream community, allowing them to include
> > > the fix if/when they are able?
> > >
> > > I believe Magnus was advocating this idea as well. See below.
> > >
> > > Best Regards
> > >
> > > Adam Farley
> > >
> > > > Same here. I would like to have this fix in, but do not want to go
> > > > over Phils head.
> > > >
> > > > I think Phil was the main objector, maybe he could reconsider?`
> > > >
> > > > Thanks, Thomas
> > > >
> > > > On Thu, Apr 26, 2018 at 10:39 AM, Magnus Ihse Bursie
> > > > <magnus.ihse.bursie at oracle.com> wrote:
> > > > > I don't object, but it's not build code so I don't have the 
> final say.
> > > > >
> > > > > /Magnus
> > > > >
> > > > >
> > > > > On 2018-04-25 17:43, Adam Farley8 wrote:
> > > > >
> > > > > Hi All,
> > > > >
> > > > > Does anyone have an objection to pushing this tiny change in?
> > > > >
> > > > > It doesn't break anything, it fixes a build break on two 
> supported
> > > > > platforms, and it seems
> > > > > like we never refresh the code from upstream.
> > > > >
> > > > > - Adam
> > > > >
> > > > >> I also advocate the source code fix, as Make isn't meant to
> > use the sort
> > > > >> of logic required
> > > > >> to properly analyse the toolchain version string.
> > > > >>
> > > > >> e.g. An "eq" match on 4.8.5 doesn't protect the user who is
> > using 4.8.6,
> > > > >> and Make doesn't
> > > > >> seem to do substring stuff unless you mess around with shells.
> > > > >>
> > > > >> Plus, as people have said, it's better to solve problem x (or
> > work around
> > > > >> a specific
> > > > >> instance of x) than to ignore the exception, even if the
> > ignoring code is
> > > > >> toolchain-
> > > > >> specific.
> > > > >>
> > > > >> - Adam Farley
> > > > >>
> > > > >> > On 2018-03-27 18:44, Phil Race wrote:
> > > > >> >
> > > > >> >> As I said I prefer the make file change, since this is a
> > change to an
> > > > >> >> upstream library.
> > > > >> >
> > > > >> > Newtons fourth law: For every reviewer, there's an equal 
> and opposite
> > > > >> > reviewer. :)
> > > > >> >
> > > > >> > Here I am, advocating a source code fix. As Thomas says, 
> the compiler
> > > > >> > complaint seems reasonable, and disabling it might cause us
> > > to miss other
> > > > >> > future errors.
> > > > >> >
> > > > >> > Why can't we push the source code fix, and also submit it 
> upstream?
> > > > >> >
> > > > >> > /Magnus
> > > > >> >
> > > > >> >
> > > > >> > I've looked at jpeg-9c and it still looks identical to 
> whatwe have in
> > > > >> > 6b, so this code
> > > > >> > seems to have stood the test of time. I'm also unclear why
> > the compiler
> > > > >> > would
> > > > >> > complain about that and not the one a few lines later
> > > > >> >
> > > > >> >
> > > > >> >  819   while (bits[i] == 0)        /* find largest
> > > codelength still in
> > > > >> > use */
> > > > >> >  820     i--;
> > > > >> >
> > > > >> > A push to jchuff.c will get blown away if/when we upgrade.
> > > > >> > A tool-chain specific fix in the makefile with an
> > appropriatecomment is
> > > > >> > more targeted.
> > > > >>
> > > > >> Phil,
> > > > >>
> > > > >> Returning to this.
> > > > >>
> > > > >> While I understand your reluctance to patch upstream code, 
> let me point
> > > > >> out that we have not updated libjpeg a single time since the
> > JDK was open
> > > > >> sourced. We're using 6b from 27-Mar-1998. I had a look at the
> > > Wikipedia page
> > > > >> on libjpeg, and this is the latest "uncontroversial" version of
> > > the source.
> > > > >> Versions 7 and up have proprietary extensions, which in turn
> > > has resulted in
> > > > >> multiple forks of libjpeg. As it stands, it seems unlikely that
> > > we will ever
> > > > >> replace libjpeg 6b with a simple upgrade from upstream.
> > > > >>
> > > > >> I therefore maintain my position that a source code fix would
> > be the best
> > > > >> way forward here.
> > > > >>
> > > > >> /Magnus
> > > > >>
> > > > >> >
> > > > >> >
> > > > >> > -phil.
> > > > >> >
> > > > >> >
> > > > >> > On 03/27/2018 05:44 AM, Thomas Stüfe wrote:
> > > > >> >
> > > > >> > Hi all,
> > > > >> >
> > > > >> >
> > > > >> > just a friendly reminder. I would like to push this tiny 
> fix because
> > > > >> > tripping over this on our linux s390x builds is annoying 
> (yes, we can
> > > > >> > maintain patch queues, but this is a constant error source).
> > > > >> >
> > > > >> >
> > > > >> > I will wait for 24 more hours until a reaction. If no
> > seriousobjections
> > > > >> > are forcoming, I want to push it (tier1 tests ran thru, and
> > > me and Christoph
> > > > >> > langer are both Reviewers).
> > > > >> >
> > > > >> >
> > > > >> > Thanks! Thomas
> > > > >> >
> > > > >> >
> > > > >> > On Wed, Mar 21, 2018 at 6:20 PM, Thomas Stüfe
> > <thomas.stuefe at gmail.com>
> > > > >> > wrote:
> > > > >> >
> > > > >> > Hi all,
> > > > >> >
> > > > >> >
> > > > >> > may I please have another review for this really trivial 
> change. It
> > > > >> > fixes a gcc warning on s390 and ppc. Also, it is probably a
> > > good idea to fix
> > > > >> > this.
> > > > >> >
> > > > >> >
> > > > >> > bug: https://bugs.openjdk.java.net/browse/JDK-8200052
> > > > >> > webrev:
> > > > >> > http://cr.openjdk.java.net/~stuefe/webrevs/8200052-fix- 
> <http://cr.openjdk.java.net/%7Estuefe/webrevs/8200052-fix->
> > > warning-in-jchuff.c/webrev.00/webrev/
> > > > >> >
> > > > >> >
> > > > >> > This was contributed by Adam Farley at IBM.
> > > > >> >
> > > > >> >
> > > > >> > I already reviewed this. I also test-built on zlinux and it 
> works.
> > > > >> >
> > > > >> >
> > > > >> > Thanks, Thomas
> > > > >> >
> > > > >>
> > > > >> Unless stated otherwise above:
> > > > >> IBM United Kingdom Limited - Registered in England and Wales
> > with number
> > > > >> 741598.
> > > > >> Registered office: PO Box 41, North Harbour, Portsmouth,
> > > Hampshire PO6 3AU
> > > > >>
> > > > >>
> > > > >
> > > > > Unless stated otherwise above:
> > > > > IBM United Kingdom Limited - Registered in England and Wales 
> with number
> > > > > 741598.
> > > > > Registered office: PO Box 41, North Harbour, Portsmouth,
> > Hampshire PO6 3AU
> > > > >
> > > > >
> > >
> > > Unless stated otherwise above:
> > > IBM United Kingdom Limited - Registered in England and Wales with
> > > number 741598.
> > > Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire 
> PO6 3AU
> >
> > Unless stated otherwise above:
> > IBM United Kingdom Limited - Registered in England and Wales with
> > number 741598.
> > Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire 
> PO6 3AU
> Unless stated otherwise above:
> IBM United Kingdom Limited - Registered in England and Wales with 
> number 741598.
> Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU

More information about the build-dev mailing list