Build dynamic library failed on Windows

[theidexisted]

Hi, I'am trying to build a dll library on Windows, but got linking error:

Severity	Code	Description	Project	File	Line	Suppression State
Error	LNK2001	unresolved external symbol __imp_listen	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\tcp_socket.obj	1	
Error	LNK1120	20 unresolved externals	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\msvc15\x64\Release\tacopie.dll	1	
Error	LNK2001	unresolved external symbol __imp_accept	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\tcp_socket.obj	1	
Error	LNK2001	unresolved external symbol __imp_bind	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\windows_self_pipe.obj	1	
Error	LNK2001	unresolved external symbol __imp_closesocket	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\windows_self_pipe.obj	1	
Error	LNK2001	unresolved external symbol __imp_connect	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\windows_self_pipe.obj	1	
Error	LNK2001	unresolved external symbol __imp_freeaddrinfo	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\windows_tcp_socket.obj	1	
Error	LNK2001	unresolved external symbol __imp_getaddrinfo	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\windows_tcp_socket.obj	1	
Error	LNK2001	unresolved external symbol __imp_getsockname	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\windows_self_pipe.obj	1	
Error	LNK2001	unresolved external symbol __imp_htonl	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\windows_self_pipe.obj	1	
Error	LNK2001	unresolved external symbol __imp_htons	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\windows_tcp_socket.obj	1	
Error	LNK2001	unresolved external symbol __imp_inet_ntoa	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\tcp_socket.obj	1	
Error	LNK2001	unresolved external symbol __imp_ioctlsocket	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\windows_self_pipe.obj	1	
Error	LNK2001	unresolved external symbol __imp_recv	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\tcp_socket.obj	1	
Error	LNK2001	unresolved external symbol __imp_recvfrom	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\windows_self_pipe.obj	1	
Error	LNK2001	unresolved external symbol __imp_select	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\io_service.obj	1	
Error	LNK2001	unresolved external symbol __imp_send	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\tcp_socket.obj	1	
Error	LNK2001	unresolved external symbol __imp_sendto	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\windows_self_pipe.obj	1	
Error	LNK2001	unresolved external symbol __imp_socket	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\windows_self_pipe.obj	1	
Error	LNK2001	unresolved external symbol __imp_WSAGetLastError	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\windows_tcp_socket.obj	1	
Error	LNK2001	unresolved external symbol __WSAFDIsSet	tacopie	Z:\cpp_redis4.2.0\cpp_redis-4.2.0\tacopie\msvc15\io_service.obj	1	

How to reproduce:

• Use latest tacopie tag(3.1.0)
• Change visual studio solution configure: Configuration Type: static to dynamic

[Cylix]

Hi,

Sorry for the late reply.

The output looks similar to the one reported on cpp_redis#46. At the time, the error was due to the fact the author was not linking with Ws2_32.lib.
If you are still having this issue, can you let me know if you are compiling with this system library? If not, can you try to link with it?

Best

[yuangu]

add this code in you project:
#pragma comment( lib, "ws2_32.lib")

[Cylix]

interested, I didn't know about that #pragma comment feature, will add

[theidexisted]

Add linkage of ws2_32.lib does not work, I get linking error still.

[yuangu]

what your compiler?

[theidexisted]

I'm using vs2015 with win server 2008

[yuangu]

@Cylix
I know what the reason。this code add to tacopie file。so not't compile into the dll (in other words， this code not wrok).

#ifdef _WIN32 #pragma comment( lib, "ws2_32.lib") #endif /* _WIN32 */

your try to add
#pragma comment( lib, "ws2_32.lib") into windows_tcp_socket.cpp files.

sorry for my english.

[yuangu]

[theidexisted]

@yuangu @Cylix
Many thanks, but it's bad to add library dependency in source code. I prefer to add ws2_32.lib in the project configuration. The configure path:
Configuration Property -> Linker -> Input -> Additional dependency.

What's more, this project lacks the exporting set for making a DLL on windows. We need to change the declaration like this:

- void set_nb_workers(std::size_t nb_threads);
+ __declspec(dllexport) void set_nb_workers(std::size_t nb_threads);

If you agree with me, I will submit a patch latter.

[Cylix]

Hi,

Sorry I missed the updates on this issue.
@yuangu I will make the change, it makes sense.
@Prehistoric-penguin you can definitely make this change, I would be happy to merge it. I would be cautious though: be careful not to break unix build.

I'm closing this issue as the original problem seems resolved.

Best