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

[Magnus Ihse Bursie]

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 what we 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 appropriate comment 
> 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 serious 
> objections 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-warning-in-jchuff.c/webrev.00/webrev/ 
> <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