Compilation issue

[harishmurkal]

Hi,

I am considering your software for the first time. I have taken the latest release Release 0.123.2.
I am getting this following error of re-definition. When fixing by removing one of the definition I'm getting other consequential errors. Just wanted to know if any flags as such available for overcoming this issue?

Thanks and Regards,
Harish M

Compilation log snippet:

Scanning dependencies of target Nim_UT
[ 94%] Building CXX object CMakeFiles/Nim_UT.dir/imsgit_local/work/harism/reg/5g_core/ngnim/src/NIM_NfNotification.cxx.o
In file included from /imsgit_local/work/harism/reg/5g_core/ngnim/jsoncons/include/jsoncons/json_exception.hpp:13:0,
from /imsgit_local/work/harism/reg/5g_core/ngnim/jsoncons/include/jsoncons/basic_json.hpp:26,
from /imsgit_local/work/harism/reg/5g_core/ngnim/jsoncons/include/jsoncons/json.hpp:10,
from /imsgit_local/work/harism/reg/5g_core/ngnim/src/NIM_NfNotification.cxx:20:
/imsgit_local/work/harism/reg/5g_core/ngnim/jsoncons/include/jsoncons/unicode_traits.hpp:1482:12: error: specialization of ‘std::is_error_code_enumjsoncons::unicons::conv_errc’ after instantiation
struct is_error_code_enumjsoncons::unicons::conv_errc : public true_type
^
/imsgit_local/work/harism/reg/5g_core/ngnim/jsoncons/include/jsoncons/unicode_traits.hpp:1482:12: error: redefinition of ‘struct std::is_error_code_enumjsoncons::unicons::conv_errc’
In file included from /imsgit/Tools/tsp_tools/CONTAINER_TOOLSET/toolset_CENTOS/usr/include/c++/4.8.2/mutex:43:0,
from /imsgit_local/work/harism/reg/ims_tools/grpc/protobuf/include/google/protobuf/stubs/mutex.h:33,
from /imsgit_local/work/harism/reg/ims_tools/grpc/protobuf/include/google/protobuf/stubs/common.h:52,
from /imsgit_local/work/harism/reg/5g_core/nimrpc/inc/NimDiscovery.pb.h:9,
from /imsgit_local/work/harism/reg/5g_core/nimrpc/inc/NimDiscovery.grpc.pb.h:22,
from /imsgit_local/work/harism/reg/5g_core/ngnim/inc/NIM_GrpcHandler.h:12,
from /imsgit_local/work/harism/reg/5g_core/ngnim/inc/NIM_Framework.h:16,
from /imsgit_local/work/harism/reg/5g_core/ngnim/src/NIM_NfNotification.cxx:6:
/imsgit/Tools/tsp_tools/CONTAINER_TOOLSET/toolset_CENTOS/usr/include/c++/4.8.2/system_error:54:12: error: previous definition of ‘struct std::is_error_code_enumjsoncons::unicons::conv_errc’
struct is_error_code_enum : public false_type { };

[danielaparker]

This is the first time we've had a report of a duplicate symbol, so I need to understand this better. Could you send me your full error log, to [email protected]?

When you say, "removing one of the definitions", do you mean removing these lines, in unicode_traits.hpp?

#ifndef JSONCONS_UNICONS_UNICODE_TRAITS_HPP
#define JSONCONS_UNICONS_UNICODE_TRAITS_HPP

#include <system_error>

// HERE
namespace std {
    template<>
    struct is_error_code_enum<jsoncons::unicons::conv_errc> : public true_type
    {
    };
    template<>
    struct is_error_code_enum<jsoncons::unicons::encoding_errc> : public true_type
    {
    };
}
#endif

That's the only place these symbols are defined, and I believe those are legal declarations. Similar declarations are used for error codes, e.g.

#ifndef JSONCONS_JSON_ERROR_HPP
#define JSONCONS_JSON_ERROR_HPP

#include <system_error>

namespace std {
    template<>
    struct is_error_code_enum<jsoncons::json_errc> : public true_type
    {
    };
}

#endif

Are you also getting redefinition errors for these?

We're currently testing linux builds on ubuntu, I'll look into setting up a build project on centos.

The specializations of is_error_code_enum in the std namespace are a convenience, but the code could
be rewritten without them, so if that's the only issue, we could look into that.

Daniel

[danielaparker]

I would need your help to pursue this further. Absent that, there's not much I can do.

[patternoia]

Dear Daniel,
I am getting very similar compilation error in c++ (Debian 4.9.2-10+deb8u2) 4.9.2. Compiling it in clang 8 (Apple LLVM version 8.0.0 (clang-800.0.42.1)) works just fine.
When I am commenting out the is_error_code_enum<jsoncons::unicons::conv_errc> : public true_type block, the compilation succeeds, I am not sure however if it will have any side effects.
I am using jsoncons version 0.122.0, upgrading to 0.133.0 does not help.

I am sending you the log files over the email.

[danielaparker]

Thanks, reopening this issue, will investigate. If it compiles, there shouldn't be any issue from commenting out the line, it's purpose is only to indicate that the type jsoncons::unicons::conv_errc is eligible for automatic conversion to std::error_code. What I don't understand is why we have two reported issues with is_error_code_enum<jsoncons::unicons::conv_errc>, but not with similar declarations in the library. But will look at it.

[danielaparker]

Hi patternoia,

Could you take master, and rebuild in Debian 4.9.2 environment? Or if you prefer, just replace jsoncons/unicode_traits.hpp with https://raw.githubusercontent.com/danielaparker/jsoncons/master/include/jsoncons/unicode_traits.hpp. Let me know if you still have the compilation error?

Thanks,
Daniel

[patternoia]

Hi Daniel, this fixes it. Thanks a lot for quick response.

[danielaparker]

Resolved in v0.134.0