Cannot call functions in a DLL

Question

So I want to make a shared library, and testing how it works... But I just don't understand what am I doing wrong here...

main.cpp:

//main.cpp
#include <iostream>

__declspec(dllimport) int foo(int);

int main() {
    std::cout << foo(5) << std::endl;
}

shared.cpp:

shared.cpp
__declspec(dllexport) int foo(int k) {
    return k;
}

Every time I tried to build, it fails with the following output: output:

[build] MSBuild version 17.7.2+d6990bcfa for .NET Framework
[build] 
[build]   MnShared.vcxproj -> D:\Programs\tst\mn\build\Debug\MnShared.dll
[build]   main.cpp
[build] main.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) int __cdecl foo(int)" (__imp_?foo@@YAHH@Z) referenced in function main
[build] D:\Programs\tst\mn\build\Debug\MN.exe : fatal error LNK1120: 1 unresolved externals
[proc] The command: "E:\Program Files\Microsoft Visual Studio\2022\Community\Common7\IDE\CommonExtensions\Microsoft\CMake\CMake\bin\cmake.exe" --build d:/Programs/tst/mn/build --config Debug --target ALL_BUILD -j 10 -- exited with code: 1
[driver] Build completed: 00:00:02.045
[build] Build finished with exit code 1

NOTE: shared.cpp and main.cpp are in the same project and are getting built in the same directory

CMakeLists.txt:

cmake_minimum_required(VERSION 3.8)
project(MN CXX)

add_executable(MN main.cpp)

add_library(MnShared SHARED shared.cpp)

Answer 1

Adding target_link_libraries(MN PRIVATE MnShared) at the bottom of CMakeLists.txt solved the problem.