error LNK2019: unresolved external symbol "void __cdecl libtorrent::rel_performancetimer_pools_nolog_resolvecountries_deprecated_dht_ext_(void)" (?rel_performancetimer_pools_nolog_resolvecountries_deprecated_dht_ext_@libtorrent@@YAXXZ) referenced in function "public: __thiscall libtorrent::session::session(struct libtorrent::fingerprint const &,int,unsigned int)" (??0session@libtorrent@@QAE@ABUfingerprint@1@HI@Z)

[GoogleCodeExporter]

What steps will reproduce the problem?
1. int main() {  libtorrent::session s; }
2.
3.

What is the expected output? What do you see instead?

What version of the product are you using? On what operating system?

Please provide any additional information below.

Original issue reported on code.google.com by a...@sipfish.com on 7 Apr 2013 at 4:07

[GoogleCodeExporter]

This is a link error by design. It's a symptom of building libtorrent with a 
different set of TORRENT_* defines than what's being used in the client program.

It's unfortunate that the API (and really, the ABI) depends on build 
configuration (and I'm working on removing these dependencies). There are two 
automatic ways around this:

1. use boost-build to build the client application. boost-build will 
automatically propagate configuration options up to dependents.

2. on unix systems, use `pkg-config --cflags libtorrent-rasterbar` for build 
flags. The pkgconfig file created by libtorrent reflects the configuration that 
was built.

On other systems, just make sure the same TORRENT_* defines are present when 
building your client application. It looks like you're on windows, in which 
case you probably should put them in your project file. To find the defines 
used, you can look in the response files (.rsp) created by boost-build when 
building libtorrent, or the command lines issued if you built with CMake or gnu 
make.

Original comment by arvid.no...@gmail.com on 7 Apr 2013 at 5:04

• Changed state: WontFix

[GoogleCodeExporter]

Understood, Thanks.

Original comment by a...@sipfish.com on 7 Apr 2013 at 5:11

[GoogleCodeExporter]

There are no defines in the *.rsp files, just reference to the objects to link 
against.
any Idea how to find out what TORRENT_* defines i need on windows?
(the client application is way to complex to be converted to boost-build)

Original comment by a...@sipfish.com on 7 Apr 2013 at 5:49

[GoogleCodeExporter]

what command line did you use to build libtorrent?

Original comment by arvid.no...@gmail.com on 7 Apr 2013 at 4:04

[GoogleCodeExporter]

b2 boost=source

Seems like the macro TORRENT_CFG in session's constructor expansion triggers 
this

Original comment by a...@sipfish.com on 7 Apr 2013 at 4:18

[GoogleCodeExporter]

Was there a solution to how to get the preprosessor defines out off a 
boost-build?

Original comment by sbstn...@gmail.com on 29 Jul 2013 at 4:42

[GoogleCodeExporter]

I've spent two days on it and finally I've found an issue.
Name of this function "void 
rel_performancetimer_pools_nolog_resolvecountries_deprecated_dht_ext_" consists 
of the parts, that describes your current preferences. For example, dht_ means 
you're using DHT, and nolog_ means you're switched off TORRENT_LOGGING 
directive.
The problem is: this settings works only with Release configuration! rel_ means 
release_. On the libtorrent 0.16.11 this problem still not solved.
I've put this text in file build_config.hpp on the line 40:
#ifdef _DEBUG
#define TORRENT_DEBUG
#endif
This is the way to compile my project with libtorrent in release and debug 
configurations, without making any corrections. 
Arvid, please, include this 3 lines to your next version of libtorrent. 
Appreciated,
Ilya from Russia.

Original comment by ilka...@gmail.com on 10 Sep 2013 at 12:58

[GoogleCodeExporter]

I don't understand what the problem is, could you describe it in more details?

if your libtorrent.dll exports the symbol starting with rel_, it means it was 
build in release mode, and that its ABI requires TORRENT_DEBUG _not_ to be set 
when including libtorrent headers.

If you go and define TORRENT_DEBUG just because you're building the client in 
debug mode, you will require the torrent.dll to also have been built in debug 
mode (and had TORRENT_DEBUG set, which isn't the case if it's exporting 
rel_...).

The point of this symbol is to make sure your client will use a compatible ABI 
as the .dll you're linking against.

Original comment by arvid.no...@gmail.com on 12 Sep 2013 at 7:04