RFR(XS): 8215009: GCC 8 compilation eror in libjli

[Dmitry Chuyko]

On 12/18/18 3:39 AM, David Holmes wrote:
> On 11/12/2018 9:30 pm, Dmitry Chuyko wrote:
>> On 12/11/18 4:03 AM, David Holmes wrote:
>>> Hi Dmitry,
>>>
>>> On 11/12/2018 12:16 am, Dmitry Chuyko wrote:
>>>> Hello,
>>>>
>>>> Please review a small fix in java_md_solinux.c: continuation is not 
>>>> truly compatible with pthread_create start_routine's signature but 
>>>> we control what actually happens. So it makes sense to add 
>>>> intermediate void* cast to silence the error.
>>>
>>> I'd be tempted to fix the signature and get rid of all the casts.
>>
>> David, the signature is a signature of
>>
>> int JNICALL JavaMain(void * _args)
>>
>> It would be fun to change it. But still on Windows it is correctly 
>> passed to _beginthreadex() and then return code is extracted with 
>> GetExitCodeThread(). In case we want it to return void* the cast will 
>> move there.
>
> I think the current double cast is truly ugly and an ifdef for 
> windows, or a cast for Windows only would be an improvement.

I agree. Maybe making a wrapper function is not so ugly. If there are no 
objections to changing beginning of the call stack it is quite easy to 
implement. For consistency it may be done for all 3 points (posix unix, 
posix mac, windows) or just for posix ones.

It looks like ifdef should be better as long as there are already 
OS-specific parts in libjli. Again, if there are no objections to have 
different JavaMain signatures on different platforms. In this case there 
won't be a signature cast for Windows.

-Dmitry

>
> But I won't impose that on you just to silence gcc 8.
>
> Cheers,
> David
>
>> -Dmitry
>>
>>>
>>> Cheers,
>>> David
>>>
>>>> bug: https://bugs.openjdk.java.net/browse/JDK-8215009
>>>> webrev: http://cr.openjdk.java.net/~dchuyko/8215009/webrev.00/
>>>> testing: submit repo 
>>>> (mach5-one-dchuyko-JDK-8215009-20181207-1625-13615: PASSED)
>>>>
>>>> -Dmitry
>>>>