RFR(S): 8043491: warning LNK4197: export '... ...' specified multiple times; using first specification

[Calvin Cheung]

Thanks for your review - Yumin.

On 11/12/2014 2:45 PM, Yumin Qi wrote:
> Looks good to me.
>
> Thanks
> Yumin
> On 11/10/2014 10:12 PM, Calvin Cheung wrote:
>> This is for fixing link warnings on windows such as the following:
>> jni.obj : warning LNK4197: export 'JNI_CreateJavaVM' specified 
>> multiple times; using first specification
>>
>> The warning is reproducible with both VS2010 and VS2013.
>> It is applicable to 64-bit only probably due to the 
>> __declspec(dllexport) on 32-bit, it exports the function decorated 
>> name with a leading underscore, but not the case on 64-bit as 
>> described in:
>> http://stackoverflow.com/questions/3572344/a-warning-with-building-64bit-dll 
>>
>>
>> All those functions are declared with JNIEXPORT (#define JNIEXPORT 
>> __declspec(dllexport)) and we're adding the /export:<function name> 
>> in the link command. Therefore, on 64-bit platform, we get the 
>> "specified multiple times" LNK4197 warning.
>>
>> A fix is to check if the platform is 64-bit, we don't add those 
>> /export option to the link command.
>>
>> JBS: https://bugs.openjdk.java.net/browse/JDK-8043491
>>
>> webrev: http://cr.openjdk.java.net/~ccheung/8043491/webrev/
>>
>> Tests:
>>     (1) build jvm.dll via command line (both 32- and 64-bit)
>>           use configure.sh to setup and then do "make CONF=<config> 
>> hotspot"
>>
>>     (2) generate visual studio project files using ProjectCreator 
>> (both 32- and 64-bit)
>>           build jvm.dll via VS2013 (both 32- and 64-bit)
>>
>>     (3) JPRT
>>
>> thanks,
>> Calvin
>>
>>
>>
>