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

[Fedor]

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
>>>>>>>>
>>>>>>
>>>