Re: [OpenJDK 2D-Dev] RFR JDK-8209786: gcc 7.3 compiler errors on zLinux

[Philip Race]

Some day, I'd like to replace a lot of medialib functionality with something
like the proposed Vector API. But that is far enough away that medialib 
needs
to be maintained, and unlike a previous discussion about a similar issue in
the JPEG library, we are on the hook for maintaining medialib.
So if there is an actual logic error in medialib, I'd prefer to fix it.
If the issue is a false positive, I'd be OK to disable the warning, but 
wrapped
in a platform-specific manner. So is it a real error here ?
-phil.

On 8/30/18, 3:37 PM, Brian Burkhalter wrote:
Hi Andrew,

As noted in the issue comments, the fdlibm C code is obsolescent and 
eventually to be superseded by equivalent Java implementations. As for 
the mediaLib code being moribund I cannot speak but am copying 2d-dev 
which owns java.desktop.

Thanks,

Brian

On Aug 30, 2018, at 6:03 AM, Andrew Leonard 
<andrew_m_leon...@uk.ibm.com <mailto:andrew_m_leon...@uk.ibm.com>> wrote:

Thanks Magnus,
Yes, these libraries are moribound it seems, hence their preference 
for compile options..
Cheers
Andrew

Andrew Leonard
Java Runtimes Development
IBM Hursley
IBM United Kingdom Ltd
Phone internal: 245913, external: 01962 815913
internet email: andrew_m_leon...@uk.ibm.com 
<mailto:andrew_m_leon...@uk.ibm.com>




From: Magnus Ihse Bursie <magnus.ihse.bur...@oracle.com 
<mailto:magnus.ihse.bur...@oracle.com>>
To: Andrew Leonard <andrew_m_leon...@uk.ibm.com 
<mailto:andrew_m_leon...@uk.ibm.com>>, Brian Burkhalter 
<brian.burkhal...@oracle.com <mailto:brian.burkhal...@oracle.com>>
Cc: core-libs-dev@openjdk.java.net 
<mailto:core-libs-dev@openjdk.java.net>, build-dev 
<build-...@openjdk.java.net <mailto:build-...@openjdk.java.net>>
Date: 30/08/2018 13:49
Subject: Re: RFR JDK-8209786: gcc 7.3 compiler errors on zLinux
------------------------------------------------------------------------



Andrew,

If you want to make changes to the build system (files in make/*),
please always include build-dev in the reviews.

From a build point, this fix looks okay. My general preference is to
fix shady code instead of disabling warnings, but in this case it's in
two libraries that are either external or moribound, so if the
maintainer's of the respective libraries want to avoid code changes, I
accept that.

/Magnus


On 2018-08-30 14:18, Andrew Leonard wrote:
> Hi Brian,
> Thanks for taking a look at this, I have just done a rebuild with a new
> patch with appropriate gcc disable warnings for these libraries:
> http://cr.openjdk.java.net/~aleonard/8209786/webrev.01/ 
<http://cr.openjdk.java.net/%7Ealeonard/8209786/webrev.01/>
> This works fine, so if you think this is a more favourable approach for
> these libraries? i'd like to get this merged please.
> Thanks
> Andrew
>
> Andrew Leonard
> Java Runtimes Development
> IBM Hursley
> IBM United Kingdom Ltd
> Phone internal: 245913, external: 01962 815913
> internet email: andrew_m_leon...@uk.ibm.com 
<mailto:andrew_m_leon...@uk.ibm.com>
>
>
>
>
> From:   Brian Burkhalter <brian.burkhal...@oracle.com 
<mailto:brian.burkhal...@oracle.com>>
> To:     Andrew Leonard <andrew_m_leon...@uk.ibm.com 
<mailto:andrew_m_leon...@uk.ibm.com>>
> Cc: core-libs-dev@openjdk.java.net 
<mailto:core-libs-dev@openjdk.java.net>
> Date:   28/08/2018 15:52
> Subject:        Re: RFR JDK-8209786: gcc 7.3 compiler errors on zLinux
>
>
>
> Hi Andrew,
>
> It was suggested that it would be preferable to dial down the 
compilation
> settings for the fdlibm code rather than make a source code change. Was
> this investigated?
>
> Thanks,
>
> Brian
>
> On Aug 28, 2018, at 7:18 AM, Andrew Leonard 
<andrew_m_leon...@uk.ibm.com <mailto:andrew_m_leon...@uk.ibm.com>>
> wrote:
>
> We have discovered issues with gcc 7.3 on zLinux, combined with 
OpenJDK's
> default compiler options has highlighted a couple of native code issues,
> with undefined behaviours:
>   - validating loop test array bounds
>   - left shifts of negative values
> I have created bug https://bugs.openjdk.java.net/browse/JDK-8209786
> and attached the webrev fix here:
> http://cr.openjdk.java.net/~aleonard/8209786/webrev.00/ 
<http://cr.openjdk.java.net/%7Ealeonard/8209786/webrev.00/>
>
> This has already been discussed and refined on the "s390x-port-dev"
> maillist
> and as it was pointed out, it should have been posted here...
>
> I'd like to request a sponsor for this fix please?
>
>
>
>
> 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