JDK 9 build with GCC 6.1.1

[Yasumasa Suenaga]

Hi Kim,

The newest changes for jdk repos is [1].
Erik points we should use DISABLED_WARNINGS_gcc to handle unknown warning tags. [2]
[1] is implemented with it.

This change is already reviewed by 2d folks.
So I want to merge it ASAP.

Do you have any objection?


Thanks,

Yasumasa


[1] http://mail.openjdk.java.net/pipermail/2d-dev/2016-June/007090.html
[2] http://mail.openjdk.java.net/pipermail/jdk9-dev/2016-June/004499.html


On 2016/06/28 8:37, Kim Barrett wrote:
>> On Jun 25, 2016, at 9:57 AM, Yasumasa Suenaga <yasuenag at gmail.com> wrote:
>>
>> Hi all,
>>
>> This review request relates to [1].
>>
>> I've tried to build OpenJDK 9 at Fedora 24 x64.
>> Fedora 24 has GCC 6.1.1, and OpenJDK 9 build was failed.
>>
>> I fixed build error and several issues (VM crash and internal error) as below:
>>
>>  http://cr.openjdk.java.net/~ysuenaga/jdk9-for-gcc6/hotspot/
>>
>> Does someone work for it?
>> If no one works for it, I will file it to JBS and will send review request.
>>
>> For jdk repos, I've sent review request [2].
>>
>>
>> Thanks,
>>
>> Yasumasa
>>
>>
>> [1] http://mail.openjdk.java.net/pipermail/jdk9-dev/2016-June/004494.html
>> [2] http://mail.openjdk.java.net/pipermail/2d-dev/2016-June/007081.html
>
> Having gone through these, I think all of them are arising due to
> build system problems, where we seem to have lost the compiler
> configuration to use explicit selection of the language standard and
> some additional options.
>
> For now I think we should fix the build system problems, and file
> additional bugs or update existing ones as needed to fix the root
> causes of the problems encountered. I think many of the proposed
> changes do not address the root causes, and should not be made.  See
> my comments for the specific bugs.
>
> I'm not on the mailing list where the jdk RFR was submitted.  I took a
> look at them though, and
>
> ------------------------------------------------------------------------------
> make/lib/Awt2dLibraries.gmk
>  407 # Avoid warning for GCC 6
>  408 ifeq ($(TOOLCHAIN_TYPE), gcc)
>  409   LCMS_CFLAGS += -Wno-misleading-indentation
>  410 endif
>
>  926     # Avoid warning for GCC 6
>  927     ifeq ($(TOOLCHAIN_TYPE), gcc)
>  928       BUILD_LIBSPLASHSCREEN_jdhuff.c_CFLAGS += -Wno-shift-negative-value
>  929       BUILD_LIBSPLASHSCREEN_jdphuff.c_CFLAGS += -Wno-shift-negative-value
>  930     endif
>
> The -Wmisleading-indentation and -Wshift-negative-value options are
> new in gcc 6. gcc has for some time (starting with gcc 4.4) silently
> ignored unrecognized -Wno-XXX options. But some folks (like SAP) are
> still using older versions. So these will need to be conditionalized
> on the gcc version.
>
> ------------------------------------------------------------------------------
> src/java.desktop/share/native/libfontmanager/layout/SunLayoutEngine.cpp
>  154   if (min < 0) min = 0;
>  155   if (max < min) max = min; /* defensive coding */
>
> [splitting the line]
>
> Seems like this would be suppressed by -Wno-misleading-indentation,
> especially since the reported warning is for that.  Why change both
> the code and the build configuration?
>
> ------------------------------------------------------------------------------
>
> The changes in AlphaMath.c and splashscreen_jpeg.c look ok.
>