RFR JDK-8209786: gcc 7.3 compiler errors on zLinux

[Magnus Ihse Bursie]

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?
>
>
>
>
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