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Date: Tue, 04 Feb 2014 18:53:59 +0100
From: Philippe Gerum <rpm@xenomai.org>
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Subject: Re: [Xenomai] [Xenomai-git] Jan Kiszka : alchemy: Replace static
 variable no_alchemy_task with macro
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Cc: xenomai-git@xenomai.org, Jan Kiszka <jan.kiszka@siemens.com>, xenomai@xenomai.org

On 02/04/2014 06:48 PM, Philippe Gerum wrote:
> On 02/04/2014 06:44 PM, Gilles Chanteperdrix wrote:
>> On 02/04/2014 06:39 PM, Philippe Gerum wrote:
>>> On 02/04/2014 06:32 PM, Gilles Chanteperdrix wrote:
>>>> On 02/04/2014 06:27 PM, Philippe Gerum wrote:
>>>>> If g++ chokes on the initializer part because it is outdated, then
>>>>> using
>>>>> old-fashioned ones may be an option. Actually, I find macroizing this
>>>>> definition quite bad.
>>>>>
>>>>> static const RT_TASK no_alchemy_task = {
>>>>> -    .handle = 0,
>>>>> -    .thread = 0
>>>>> +    handle: 0,
>>>>> +    thread: 0
>>>>>     };
>>>>
>>>> No, the previous version is better, it is standard compliant C and C++,
>>>> the second version is a gcc extension, which works only when compiling
>>>> C, if I remember correctly.
>>>>
>>>
>>> Recent g++ is happy with both (no -std forced though). But the former is
>>> allowed by the C++ parser only since recently.
>>>
>>
>> Well, on the other hand:
>> static const RT_TAKS no_alchemy_task;
>>
>> Will zero initialized the structure just as well...
>>
>
> In that case you will have the object exist in the .bss.
>

It turns out that old gcc 4.x releases will create a private bss entry 
for this symbol in any case, which recent ones won't produce regardless 
of the optimizing level (unless I messed up with nm, but it does not 
seem so).

-- 
Philippe.