RFR: JDK-8211071: unpack.cpp fails to compile with statement has no effect [-Werror=unused-value]

[Roman Kennke]

Hi Christoph & Magnus, thanks for reviewing!

Am 27.09.18 um 08:22 schrieb Langer, Christoph:
> Hi Roman,
> 
> this looks good to me. +1
> 
> Best regards
> Christoph
> 
>> -----Original Message-----
>> From: build-dev <build-dev-bounces at openjdk.java.net> On Behalf Of
>> Roman Kennke
>> Sent: Mittwoch, 26. September 2018 19:24
>> To: Magnus Ihse Bursie <magnus.ihse.bursie at oracle.com>; core-libs-
>> dev at openjdk.java.net
>> Cc: build-dev at openjdk.java.net
>> Subject: Re: RFR: JDK-8211071: unpack.cpp fails to compile with statement
>> has no effect [-Werror=unused-value]
>>
>> Ping core-libs?
>>
>> Roman
>>
>> Am 25.09.18 um 11:06 schrieb Magnus Ihse Bursie:
>>>
>>>> 25 sep. 2018 kl. 10:21 skrev Roman Kennke <rkennke at redhat.com>:
>>>>
>>>> Not sure this is the correct list. Please redirect as appropriate.
>>>
>>> I believe core-libs is the appropriate place. Cc:d.
>>>
>>>>
>>>> Please review the following proposed change:
>>>>
>>>>
>>>> There are 3 asserts in unpack.cpp which check only constants, and which
>>>> the compiler rejects as 'has no effect' (in fastdebug builds). This
>>>> seems to be caused by:
>>>>
>>>> https://bugs.openjdk.java.net/browse/JDK-8211029
>>>>
>>>> I propose to fix this by defining a STATIC_ASSERT which can evaluate and
>>>> reject this at compile time:
>>>>
>>>> Webrev:
>>>> http://cr.openjdk.java.net/~rkennke/JDK-8211071/webrev.00/
>>>
>>> From a build perspective, this looks good. But please let someone from
>> core-libs review also.
>>>
>>>> Bug:
>>>> https://bugs.openjdk.java.net/browse/JDK-8211071
>>>>
>>>> It might be useful to define the STATIC_ASSERT in a more central place
>>>> to be used elsewhere too. For example, there is a similar #define in
>>>> Hotspot's debug.hpp
>>>
>>> Unfortunately, we do not have a good place to share definitions like this
>> across JDK libraries. :-( The need for that has struck me more than once. For
>> some stuff, we mis-use jni.h. But it would definitely be out of line to add a
>> STATIC_ASSERT there.
>>>
>>> /Magnus
>>>
>>>>
>>>> Thanks, Roman
>>>>
>>>
>