suggesting fix: cross-compilation is requiring write permissions to bootstrap jdk

[Claes Redestad]

Ok, I filed a bug and sponsor your patch here:

https://mail.openjdk.java.net/pipermail/build-dev/2020-June/027577.html

Hope you think it looks good. Erik suggested a few line breaks.

Thanks!

/Claes

On 2020-06-01 16:01, Fedor wrote:
> I haven't committers rights so help would be great!
> As far as I know there is no bug for described problem yet
> 
> Thanks,
> Fedor
> 
> On 01.06.2020 16:29, Erik Joelsson wrote:
>> Fix looks good to me then.
>>
>> Do you need sponsoring help? Is there a bug number for this yet?
>>
>> /Erik
>>
>> On 2020-06-01 01:53, Claes Redestad wrote:
>>> Hi Fedor,
>>>
>>> thanks for verifying!
>>>
>>> /Claes
>>>
>>> On 2020-06-01 10:39, Fedor wrote:
>>>> Hi Claes,
>>>>
>>>> The content of classlist files is the same in both cases (before and 
>>>> after change).
>>>>
>>>> And the change with updated file name $@.classlist => $@.interim as 
>>>> suggested before.
>>>>
>>>> diff --git a/make/GenerateLinkOptData.gmk 
>>>> b/make/GenerateLinkOptData.gmk
>>>> --- a/make/GenerateLinkOptData.gmk
>>>> +++ b/make/GenerateLinkOptData.gmk
>>>> @@ -69,10 +69,10 @@
>>>>              -Duser.language=en -Duser.country=US \
>>>>              -cp $(SUPPORT_OUTPUTDIR)/classlist.jar \
>>>>              build.tools.classlist.HelloClasslist $(LOG_DEBUG)
>>>> -       $(GREP) -v HelloClasslist $@.raw > 
>>>> $(INTERIM_IMAGE_DIR)/lib/classlist
>>>> -       $(FIXPATH) $(INTERIM_IMAGE_DIR)/bin/java -Xshare:dump \
>>>> +       $(GREP) -v HelloClasslist $@.raw > $@.interim
>>>> +       $(FIXPATH) $(INTERIM_IMAGE_DIR)/bin/java -Xshare:dump 
>>>> -XX:SharedClassListFile=$@.interim -XX:SharedArchiveFile=$@.jsa \
>>>>              -Xmx128M -Xms128M $(LOG_INFO)
>>>> -       $(FIXPATH) $(INTERIM_IMAGE_DIR)/bin/java 
>>>> -XX:DumpLoadedClassList=$@.raw \
>>>> +       $(FIXPATH) $(INTERIM_IMAGE_DIR)/bin/java 
>>>> -XX:DumpLoadedClassList=$@.raw -XX:SharedClassListFile=$@.interim 
>>>> -XX:SharedArchiveFile=$@.jsa \
>>>>              -Djava.lang.invoke.MethodHandle.TRACE_RESOLVE=true \
>>>>              -Duser.language=en -Duser.country=US \
>>>>              --module-path $(SUPPORT_OUTPUTDIR)/classlist.jar \
>>>>
>>>>
>>>>
>>>> Thanks,
>>>> Fedor
>>>>
>>>> On 26.05.2020 18:39, Claes Redestad wrote:
>>>>> Hi,
>>>>>
>>>>> I think the proposed flags should do the right thing here. It 
>>>>> should be
>>>>> straightforward to verify since the contents of the generated files
>>>>> should ideally not change at all on a standard build.
>>>>>
>>>>> /Claes
>>>>>
>>>>> On 2020-05-26 17:25, Erik Joelsson wrote:
>>>>>> Hello,
>>>>>>
>>>>>> On 2020-05-26 08:00, Magnus Ihse Bursie wrote:
>>>>>>>> On 26/05/2020 11:14 pm, Fedor wrote:
>>>>>>>>> Hello all!
>>>>>>>>>
>>>>>>>>> I've tried to crossbuild jdk using current 
>>>>>>>>> http://hg.openjdk.java.net/jdk/jdk/ sources and noticed that 
>>>>>>>>> build requires write permissions to bootstrap jdk.
>>>>>>
>>>>>> Your patch seems to be doing the right thing. I would just like to 
>>>>>> have Claes verify that the JVM options you are setting are 
>>>>>> actually having the desired effect. We really shouldn't be putting 
>>>>>> any files in the INTERIM_IMAGE_DIR as that can possibly be located 
>>>>>> outside the build directory. Only thing I would want to change is 
>>>>>> the suffix for the file you call $@.classlist, since $@ is already 
>>>>>> named "classlist", I would prefer something like $@.tmp or 
>>>>>> $@.interim, to signal that this is the interim result between the 
>>>>>> two generation steps.
>>>>>>
>>>>>> Then just to clarify, it's not the BOOT_JDK, but the BUILD_JDK, 
>>>>>> which is a different concept. This can get tricky so it's 
>>>>>> important to keep the definitions correct. The BOOT_JDK, which is 
>>>>>> required to be of version N-1, or possibly N, is used to build a 
>>>>>> bootstrap version of the javac compiler, which we can then run on 
>>>>>> the BOOT_JDK to compiler the JDK N java code. We also use it to 
>>>>>> run most build tools in the build.
>>>>>>
>>>>>> The BUILD_JDK is a concept introduced for cross compiling. In a 
>>>>>> native build, certain build steps are required to be performed 
>>>>>> with the newly built JDK. This includes running jmod and jlink as 
>>>>>> well as generating data used to optimize the JDK image in the 
>>>>>> jlink step (which is where you are seeing this issue). For a 
>>>>>> native build, the BUILD_JDK is simply the exploded image jdk we 
>>>>>> just built. When cross compiling, the default behavior is to just 
>>>>>> also build enough of the native parts of the JDK for the build 
>>>>>> platform and use that. You may also supply a BUILD_JDK when 
>>>>>> configuring a cross compilation build. When doing so you must 
>>>>>> ensure that it's built from the exact same sources as the JDK you 
>>>>>> are cross compiling, otherwise results are unpredictable.
>>>>>>
>>>>>> In our internal build setups, we don't use the external BUILD_JDK 
>>>>>> feature, which is why we have not run into the problem you are 
>>>>>> reporting here.
>>>>>>
>>>>>> /Erik
>>>>>>
>>>>>>>>> The problem is it tries to write/rewrite class list into 
>>>>>>>>> bootstrap jdk directory.
>>>>>>>
>>>>>>> No, it should write to the INTERIM_IMAGE_DIR.
>>>>>>>
>>>>>>> However, I now see that we replace INTERIM_IMAGE_DIR with 
>>>>>>> BUILD_JDK in GenerateLinkOptData.gmk if we have an external 
>>>>>>> build-jdk. I assume that is how you have configured. I also 
>>>>>>> assume you are not cross-compiling.
>>>>>>>
>>>>>>> I'm not entirely sure about the thinking here. I can't say for 
>>>>>>> certain that we really should run HelloClasslist if we have an 
>>>>>>> external build-jdk. I think I need Erik or Claes to chime in.
>>>>>>>
>>>>>>> /Magnus
>>>>>>>
>>>>>>>
>>>>>>>>> I would like to suggest the fix below to solve this problem:
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> diff --git a/make/GenerateLinkOptData.gmk 
>>>>>>>>> b/make/GenerateLinkOptData.gmk
>>>>>>>>> --- a/make/GenerateLinkOptData.gmk
>>>>>>>>> +++ b/make/GenerateLinkOptData.gmk
>>>>>>>>> @@ -69,10 +69,10 @@
>>>>>>>>>              -Duser.language=en -Duser.country=US \
>>>>>>>>>              -cp $(SUPPORT_OUTPUTDIR)/classlist.jar \
>>>>>>>>>              build.tools.classlist.HelloClasslist $(LOG_DEBUG)
>>>>>>>>> -       $(GREP) -v HelloClasslist $@.raw > 
>>>>>>>>> $(INTERIM_IMAGE_DIR)/lib/classlist
>>>>>>>>> -       $(FIXPATH) $(INTERIM_IMAGE_DIR)/bin/java -Xshare:dump \
>>>>>>>>> +       $(GREP) -v HelloClasslist $@.raw > $@.classlist
>>>>>>>>> +       $(FIXPATH) $(INTERIM_IMAGE_DIR)/bin/java -Xshare:dump 
>>>>>>>>> -XX:SharedClassListFile=$@.classlist 
>>>>>>>>> -XX:SharedArchiveFile=$@.jsa \
>>>>>>>>>              -Xmx128M -Xms128M $(LOG_INFO)
>>>>>>>>> -       $(FIXPATH) $(INTERIM_IMAGE_DIR)/bin/java 
>>>>>>>>> -XX:DumpLoadedClassList=$@.raw \
>>>>>>>>> +       $(FIXPATH) $(INTERIM_IMAGE_DIR)/bin/java 
>>>>>>>>> -XX:DumpLoadedClassList=$@.raw 
>>>>>>>>> -XX:SharedClassListFile=$@.classlist 
>>>>>>>>> -XX:SharedArchiveFile=$@.jsa \
>>>>>>>>> -Djava.lang.invoke.MethodHandle.TRACE_RESOLVE=true \
>>>>>>>>>              -Duser.language=en -Duser.country=US \
>>>>>>>>>              --module-path $(SUPPORT_OUTPUTDIR)/classlist.jar \
>>>>>>>>>
>>>>>>>>> Please correct me in case if it is wrong alias, or I need to 
>>>>>>>>> file bug first, or something else.
>>>>>>>>>
>>>>>>>>> Best Regards,
>>>>>>>>> Fedor
>>>>>>>>>
>>>>>>>
>>>>
>