链接器错误LNK2019？

Question

I have the following files

file1_moduleA.hpp

file1_moduleA.cpp

sharedFile.hpp

file1_moduleB.cpp

//sharedFile.hpp
extern CustomClass *doSomething(CustomClass *var1, const char *var2);
extern CustomClass *doSomethingElse(const char *var1);

template <class MYCLASS_A>
void myFunction(CustomClass *var1, const char* var2){
assert(somthing);
if (condition){
    new (MYCLASS_A);
}
}



//file1_moduleA.cpp
#include "sharedFile.hpp"
// Contains the definitions of doSomething and doSomethingElse among others


//file1_moduleA.hpp
// Other declarations


//file1_moduleB.cpp
#include"sharedFile.hpp"

//...SNIPPETS OF CODE
void someFunction(CustomClass* var1){
doSomething(var1, "FOO");
}
//...

The following are in one Visual Studio Project, Project A: file1_moduleA.hpp, file1_moduleA.cpp and sharedFile.hpp

The following are in another VS Project, Project B: file1_moduleB.cpp, file1_moduleB.hpp

Project A compiles and links perfectly, whereas Project B compiles but gives an unresolved symbol for CustomClass *doSomething(CustomClass *var1, const char *var2) at someFunction in file1_moduleB.cpp

I have tried defining the function with and without extern; tried using a separate file for the template in file1_moduleA.hpp; tried inducing dependency between ProjectB and ProjectA in VS, but nothing seems to work. I am unsure why the definition is not being found during linking. ProjectA.lib however, is being created.

Any help in this regard would be appreciated.

Answer 1

if you are using visual studio, and these are different project, then make project B dependent upon project A.

Right click on the solution. Go to project dependencies.

Choose Project B.

Click Project A (making project B dependent upon Project A)

rebuild.

Answer 2

您是否在项目B中包含共享文件？