RFR: 8157490: null stream->source() no longer causes error with -Xlog:class+load

[Max Ockner]

I like this suggestion and I have updated my fix with it.
webrev: http://cr.openjdk.java.net/~mockner/8157490.02/
Thanks,
Max

On 5/26/2016 3:12 PM, Lois Foltan wrote:
>
> On 5/26/2016 2:07 PM, Max Ockner wrote:
>> Hello,
>>
>> Please review this very small fix for class+load logging with modules.
>>
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8157490
>> Webrev: http://cr.openjdk.java.net/~mockner/8157490/
>>
>> Summary:  The JCK test 
>> vm/jni/DefineClass/dfcl001/dfcl00101m1/dfcl00101m1 hit a SIGSEGV in 
>> the logging section at the end of 
>> ClassFileParser::fill_instance_klass(). With the addition of modules, 
>> this logging section now uses
>>
>>     strlen(stream->source())
>>
>> to compute some of the module related parameters that it needs. This 
>> SIGSEGV originated from the above line being executed with a null 
>> stream source.
>
> Hi Max,
>
> I think you change is correct, but I would like to suggest changing 
> the code even further.  Currently the code between line #5352-5360 
> does a complicated check to see if the module's name is part of the 
> java runtime image file and only sets the local variable "module_name" 
> if it is.  So, only module names that are defined within the java 
> runtime image file are printed out in the logging. We should print out 
> all modules' names, not just the ones in the jimage file.  So please 
> try removing lines #5352-5360 and set the local variable to:
>
>     const char* module_name = (module_entry->name() == NULL) ? 
> UNNAMED_MODULE : module_entry->name()->as_C_string();
>
> The local variable "module_entry" is already checked at line #5310 to 
> make sure it is set to a non-NULL value.
>
> Thanks,
> Lois
>
>>
>> Tested with vm/jni/DefineClass/dfcl001/dfcl00101m1/dfcl00101m1
>>
>> Thanks,
>> Max
>