RFR: 8236714: enable link-time section-gc for linux to remove unused code

[Erik Joelsson]

Looks good.

/Erik

On 2020-01-24 01:27, Baesken, Matthias wrote:
> Hi Erik, thanks for the comments, new webrev :
>
> http://cr.openjdk.java.net/~mbaesken/webrevs/8236714.7/
>
> Best regards, Matthias
>
>
>
>> Hello,
>>
>> That's better, but there are still some issues.
>>
>> flags-cflags.m4
>>
>> Code is repeated in both if and else block.
>>
>> jdk-options.m4
>>
>> The default is now true for all platforms. I would suggest moving the
>> s390x conditional down into an elif after the elif for "no".
>>
>> LibCommon.gmk
>>
>> Please revert whole file.
>>
>> /Erik
>>
>> On 2020-01-23 05:15, Baesken, Matthias wrote:
>>> Hi Erik,  new webrev :
>>>
>>> http://cr.openjdk.java.net/~mbaesken/webrevs/8236714.6/
>>>
>>> I moved the settings back into the  m4 files .
>>>
>>> Best regards, Matthias
>>>
>>>> Hello Matthias,
>>>>
>>>> You can keep the setting up of all the flags in flags-cflags.m4 and
>>>> flags-ldflags.m4 based on the value of ENABLE_LINKTIME_GC. You can
>> also
>>>> default the value of this new parameter to true for s390x to keep the
>>>> current behavior for that platform. As it is in this patch, the JVM
>>>> flags for s390x are setup in configure while the JDK flags are in make,
>>>> which gets confusing I think.
>>>>
>>>> /Erik
>>>>
>>>>
>>>> On 2020-01-22 05:33, Baesken, Matthias wrote:
>>>>> Hi Magnus / David,  here is a new webrev :
>>>>>
>>>>>
>>>>> http://cr.openjdk.java.net/~mbaesken/webrevs/8236714.4/
>>>>>
>>>>>
>>>>> it supports now a  configure switch  --enable-linktime-gc=yes  that needs
>> to
>>>> be set  to enable the link time section gc  .
>>>>> Exception is linuxs390x  where we already have the  feature enabled
>> (and
>>>> keep it enabled always for LIB_JVM).
>>>>> Best regards, Matthias
>>>>>
>>>>>
>>>>>
>>>>> From: Baesken, Matthias
>>>>> Sent: Freitag, 17. Januar 2020 12:44
>>>>> To: Magnus Ihse Bursie <magnus.ihse.bursie at oracle.com>; David
>> Holmes
>>>> <david.holmes at oracle.com>; 'build-dev at openjdk.java.net' <build-
>>>> dev at openjdk.java.net>; 'hotspot-dev at openjdk.java.net' <hotspot-
>>>> dev at openjdk.java.net>
>>>>> Subject: RE: RFR: 8236714: enable link-time section-gc for linux to
>> remove
>>>> unused code
>>>>>
>>>>>      *   Matthias: Have a look at some recently added option to get an
>>>> indication of the best practice in adding new options. There are some
>> ways to
>>>> easily make this incorrect
>>>>> Hi Magnus, do you have a good/”best practice”  example  (not that I
>> catch a
>>>> bad one 😉 )  ?
>>>>> Best regards, Matthias
>>>>>