RFR (s) : 8145740: Visual Studio pragmas should be guarded by #ifdef _MSC_VER

[David Holmes]

We seem a bit inconsistent about how we guard compiler specific pragma's 
in shared code, but the use of _MSC_VER does already exist so this 
change seems fine to me.

I will sponsor it.

Thanks,
David

On 26/01/2016 2:58 AM, Volker Simonis wrote:
> Hi Matthias,
>
> this fix is good!
>
> The change was initially introduced to appease the Visual Studio
> compiler. But we shouldn't do that at the cost of provoking warnings
> with other compilers. Compiler specific pragmas in shared code should
> be guarded appropriately. Alternatively, we could also disable this
> warning globally on Windows by placing the pragma into
> globalDefinitions_visCPP.hpp.
>
> Either way, we need a sponsor. David, maybe you can assist?
>
> Here's a link to the initial bug which introduced this code:
>
> https://bugs.openjdk.java.net/browse/JDK-8074895
>
> The corresponding review thread states:
>
> Microsoft describes it as an obsolete warning:
>
>      https://msdn.microsoft.com/en-us/library/wewb47ee.aspx
>
>      "This warning is obsolete. It is only generated in Visual Studio
>      2005 through Visual Studio 2012. It reports a behavior change from
>      the Visual C++ compiler that shipped in Visual Studio .NET when
>      initializing a POD (plain old data) object with (); the compiler
>      default-initializes the object.”
>
> Thank you and best regards,
> Volker
>
>
> On Mon, Jan 25, 2016 at 5:37 PM, Baesken, Matthias
> <matthias.baesken at sap.com> wrote:
>> Ping .... any reviewers ??
>>
>> Best regards, Matthias
>>
>> -----Original Message-----
>> From: Langer, Christoph
>> Sent: Montag, 21. Dezember 2015 23:18
>> To: Baesken, Matthias <matthias.baesken at sap.com>; hotspot-dev at openjdk.java.net
>> Cc: Simonis, Volker <volker.simonis at sap.com>
>> Subject: RE: RFR (s) : 8145740: Visual Studio pragmas should be guarded by #ifdef _MSC_VER
>>
>> Hi Matthias,
>>
>> to me your change looks good. However, I'm no reviewer so you'll need sponsorship from someone else.
>>
>> Can someone please sponsor this? Should it maybe be posted in another list for better visibility?
>>
>> Best regards
>> Christoph
>>
>> -----Original Message-----
>> From: hotspot-dev [mailto:hotspot-dev-bounces at openjdk.java.net] On Behalf Of Baesken, Matthias
>> Sent: Freitag, 18. Dezember 2015 14:30
>> To: hotspot-dev at openjdk.java.net
>> Cc: Simonis, Volker <volker.simonis at sap.com>
>> Subject: RFR (s) : 8145740: Visual Studio pragmas should be guarded by #ifdef _MSC_VER
>>
>> Hello,
>>     can you please review and sponsor this change :
>>
>> https://bugs.openjdk.java.net/browse/JDK-8145740
>> http://cr.openjdk.java.net/~clanger/webrevs/8145740.0/
>>
>> Some details :
>>
>>       while  Visual Studio pragmas in shared code are usually guarded with  _MSC_VER in the hotspot codebase
>> ( see for example   taskqueue.hpp or  compressedStream.cpp ) , the guarding is missing in   src/share/vm/utilities/growableArray.hpp  ,
>> which is not really a "good thing"  for other compilers .
>>
>>
>> Thanks and regards, Matthias
>>