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

Mon Jun 1 08:53:05 UTC 2020

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
>>>>>>
>>>>
> 