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

[Calvin Cheung]

Thanks for your review - Christian.

Calvin

On 11/12/2014 12:53 PM, Christian Tornqvist wrote:
> Hi Calvin,
>
> Change looks good, thanks for fixing this.
>
> Thanks,
> Christian
>
> -----Original Message-----
> From: hotspot-runtime-dev
> [mailto:hotspot-runtime-dev-bounces at openjdk.java.net] On Behalf Of Calvin
> Cheung
> Sent: Tuesday, November 11, 2014 1:13 AM
> To: hotspot-runtime-dev at openjdk.java.net
> Subject: RFR(S): 8043491: warning LNK4197: export '... ...' specified
> multiple times; using first specification
>
> 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
>
>
>
>