Re: [Boost-users] [Exception] Duplicate symbol error when using errinfo_api_function in static library

Subject: Re: [Boost-users] [Exception] Duplicate symbol error when using errinfo_api_function in static library
From: Georg Leidinger (georg.leidinger_at_[hidden])
Date: 2013-10-03 03:16:55

I finally found a way to compile it with clang. I am using the pragma to
make the symbols for the Boost.Exception part not hidden like this:

#pragma GCC visibility push(default)
#include <boost/exception/all.hpp>
#pragma GCC visibility pop
*
*

- Georg Leidinger

2013/10/3 Georg Leidinger <georg.leidinger_at_[hidden]>

> I found this *clang bug* http://llvm.org/bugs/show_bug.cgi?id=10113 which
> seems to be related to the problem.
>
>
> 2013/10/3 Georg Leidinger <georg.leidinger_at_[hidden]>
>
>> It happens only if the library is build with the *LLVM 4.2* (I am using
>> XCode so it is the Apple LLVM 4.2, I don't know if there is something
>> different from the standard LLVM 4.2). If I choose the *LLVM GCC 4.2* no
>> errors are reported. Is this a bug in the LLVM compiler?
>>
>> best
>> Georg Leidinger
>>
>> 2013/10/3 Emil Dotchevski <emildotchevski_at_[hidden]>
>>
>>> On Wed, Oct 2, 2013 at 3:06 PM, Georg Leidinger <
>>> georg.leidinger_at_[hidden]> wrote:
>>>
>>>> Hi Emil,
>>>>
>>>> I was able to figure out some more information about the issue and I
>>>> could isolate it a little bit more. First it doesn't matter if it is a
>>>> static or a shared library. Second it is not directly related to the *
>>>> Boost.Exception* library but to the template class *error_info* which
>>>> is used to create the predefined errinfo_xyz types. It is enough to
>>>> instantiate the *errinfo_api_function* type in both doSomething()
>>>> methods in the both implementation files. I am not so good in templates but
>>>> I guess that the compiler creates the same symbol in both object files
>>>> (ClassA.o and ClassB.o) for the type *errinfo_api_function.* I can see
>>>> this via nm that I have the following line in both object files:
>>>>
>>>> *ClassA.o*
>>>> *0000000000059860 s __ZTIN5boost21errinfo_api_function_E*
>>>> *
>>>> *
>>>> *ClassB.o*
>>>> *0000000000059870 s __ZTIN5boost21errinfo_api_function_E *
>>>>
>>>
>>> Instantiating a template in two compilation units should not lead to
>>> link errors. That's why I can't understand why this happens.
>>>
>>> --
>>> Emil Dotchevski
>>> Reverge Studios, Inc.
>>> http://www.revergestudios.com/reblog/index.php?n=ReCode
>>>
>>> _______________________________________________
>>> Boost-users mailing list
>>> Boost-users_at_[hidden]
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>>>
>>
>>
>