[CMake] Link and build to DLL under Windows with NMake

[Micha Renner]

Your library symbols are not getting exported.

Please, look http://www.cmake.org/Wiki/BuildingWinDLL

Greeting
Micha


Am Freitag, den 20.11.2009, 13:34 +0100 schrieb Andrea Gualano:
> Hello,
> I am trying to build a .dll file under Windows and then build some test
> executable just to be sure that it works correctly.
> The source is C++, and I am trying to link to a class defined inside the
> shared library.
> This is probably very basic, but I know very little about Windows
> development and Google didn't help me.
> 
> This is my test project (full source and CMakeLists):
> 
> # top level CmakeLists.txt
> PROJECT(HELLO)
> CMAKE_MINIMUM_REQUIRED(VERSION 2.6)
> ADD_SUBDIRECTORY(src)
> ADD_SUBDIRECTORY(test)
> 
> # src/CmakeLists.txt
> ADD_LIBRARY(hello SHARED hello.cpp)
> 
> // src/hello.cpp
> #include "hello.h"
> #include <iostream>
> 
> void Hello::sayHello() {
>    std::cout << "Hello, world!" << std::endl;
> }
> 
> // src/hello.h
> #ifndef _hello_h
> #define _hello_h
> 
> class Hello {
> public:
>    void sayHello();
> };
> 
> #endif
> 
> # test/CmakeLists.txt
> INCLUDE_DIRECTORIES(${HELLO_SOURCE_DIR}/src)
> ADD_EXECUTABLE(test test.cpp)
> TARGET_LINK_LIBRARIES(test hello)
> 
> // test.cpp
> #include "hello.h"
> 
> int main() {
>    Hello().sayHello();
> }
> 
> 
> This project builds correctly under Linux, but when I try to build it
> under Windows with NMake, I get the following:
> 
> Scanning dependencies of target hello
> [ 50%] Building CXX object src/CMakeFiles/hello.dir/hello.cpp.obj
> hello.cpp
> Linking CXX shared library hello.dll
> [ 50%] Built target hello
> Scanning dependencies of target test
> [100%] Building CXX object test/CMakeFiles/test.dir/test.cpp.obj
> test.cpp
> NMAKE : fatal error U1073: don't know how to make 'src\hello.lib'
> Stop.
> NMAKE : fatal error U1077: '"C:\Program Files\Microsoft Visual Studio
> 9.0\VC\BIN\nmake.exe"' : return code '0x2'
> Stop.
> NMAKE : fatal error U1077: '"C:\Program Files\Microsoft Visual Studio
> 9.0\VC\BIN\nmake.exe"' : return code '0x2'
> Stop.
> 
> That is, the DLL is built correctly but it can't be linked to because
> there is no .lib file.
> So the question is: how do I create a .lib file so that the executable
> can be built?
> 
> The project builds if I say STATIC instead of SHARED, though what I want
> is a DLL.
> 
> Thanks and best regards,
> Andrea
>