RFR JDK-8209786: gcc 7.3 compiler errors on zLinux

[Brian Burkhalter]

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As noted in the issue comments, the fdlibm C code is obsolescent and eventually to be superseded by equivalent Java implementations.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_leonard at 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_leonard at uk.ibm.com 
> 
> 
> 
> 
> From:        Magnus Ihse Bursie <magnus.ihse.bursie at oracle.com> 
> To:        Andrew Leonard <andrew_m_leonard at uk.ibm.com>, Brian Burkhalter <brian.burkhalter at oracle.com> 
> Cc:        core-libs-dev at openjdk.java.net, build-dev <build-dev at 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/
> > 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_leonard at uk.ibm.com
> >
> >
> >
> >
> > From:   Brian Burkhalter <brian.burkhalter at oracle.com>
> > To:     Andrew Leonard <andrew_m_leonard at uk.ibm.com>
> > Cc:     core-libs-dev at 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_leonard at 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/
> >
> > 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