Re: [Xenomai] panic macro interference with xerces api.

[Philippe Gerum <rpm@xenomai.org>]

On 11/12/2015 08:37 AM, Stéphane ANCELOT wrote:
> On 11/11/2015 13:35, Philippe Gerum wrote:
>> On 11/11/2015 01:28 PM, Philippe Gerum wrote:
>>> On 11/11/2015 12:52 PM, Philippe Gerum wrote:
>>>> On 11/11/2015 11:31 AM, Jan Kiszka wrote:
>>>>> On 2015-11-10 15:28, Gilles Chanteperdrix wrote:
>>>>>> On Tue, Nov 10, 2015 at 02:26:54PM +0100, Stéphane ANCELOT wrote:
>>>>>>> Hi,
>>>>>>>
>>>>>>> I don't know if there might be a  big impact, but I noticed,
>>>>>>> depending
>>>>>>> on the order we include headers , that
>>>>>>> there was a panic macro interfering with xercesc api headers.
>>>>>>>
>>>>>>> #include <alchemy/task.h>
>>>>>>> #include <xercesc/dom/DOMException.hpp>
>>>>>>>
>>>>>>>
>>>>>>> /usr/xenomai-3.0-igb/include/boilerplate/ancillaries.h:64:10: error:
>>>>>>> expected identifier before '__func__'
>>>>>>>     __panic(__func__, __fmt, ##__args)
>>>>>> Well, if the two headers define the same macro, there are not many
>>>>>> solutions: arrange for not having to include them in the same file.
>>>>>> It should not be too hard, since a real-time thread using
>>>>>> alchemy/task.h has no business using an xml library, probably only
>>>>>> using linux services which a real-time task can not use without
>>>>>> switching to secondary mode.
>>>>> Isn't *panic an internal service? Then we can maybe avoid that it is
>>>>> exposed to applications. If it's not internal, it should probably
>>>>> carry
>>>>> some "xenomai" prefix in its (fairly generic) name.
>>>>>
>>>> Sure, this service is aimed at being fairly generic and
>>>> general-purpose,
>>>> with backtracing support, timing data, error code translation and such.
>>>> With respect to layering, I would rather expect an XML lib not to mess
>>>> with the namespace of core services, instead of asking the xenomai libs
>>>> which do deliver core services to apps to prefix its own services.
>>>>
>>>> I may move those helpers in some specific file to hide them, but no, I
>>>> really don't want to go for xenomai_panic(), because it really should
>>>> work the other way around (although nobody is likely to care about this
>>>> on the apache side).
>>>>
>>> Actually, the only issue is about defining the panic helpers as macros,
>>> so that we can pull the source/line information automatically.
>>>
>> We are not even doing that anymore, so this is eventually about moving
>> these helpers in some header that would not be pulled indirectly, or
>> using a different internal identifier from the reserved namespace.
>>
> I ordered differently the headers to enable compilation.
> I may arrange source code , since the xerces lib is needed only for data
> parsing  during the setup process.

This change from the stable branch should prevent the conflict from
arising. Including boilerplate/ancillaries.h is now required to pull the
related definitions (no more indirect inclusion from the API headers),
which should limit the scope of conflict to direct users of the
ancillaries services.

http://git.xenomai.org/xenomai-3.git/commit/?h=stable-3.0.x&id=5c88a11c11e9a2b13be4da91624dc3f3ff323e46

-- 
Philippe.