Linking of static lib with another static lib and use the master lib in a exe

Question

In eclipse I have done the below in windows platform with MinGW compiler - C_proj.exe--->links---->libB_proj.a----->links---->libA_proj.a

1. When linking A with B I am specifying only the path to libA_proj.a (not the lib name because that is not possible it seems!)

2. When making use of B inside C I had to specify both the libA_proj.a and libB_proj.a.

Codes -

//a.h
    class a
    {
    public:
        void printA();
    };

//a.cpp    
    void a::printA()
    {
        std::cout<<"This is 'a'"<<std::endl;
    }
//b.h
    class b
    {
    public:
        void printB();
        void printA();
    };
//b.cpp
    void b::printB()
    {
        std::cout<<"This is 'B'"<<std::endl;
    }

    void b::printA()
    {
        std::cout<<"This is 'B'....calling A"<<std::endl;
        a objA;
        objA.printA();
    }

//c.cpp    
    int main()
    {
        b objB;
        objB.printB();
        objB.printA();
        return 0;
    }

Now my requirement is -- I don't want to link both B and A with C exe. Is there a way to link only B with C and get the work done so that I can provide only B and C exe to a third party?

Answer 1

A lib-file (or .a file) is a collection of object files - a bit like a zip-file, but with no compression. So you can't really LINK an lib file with another lib file.

What you can do is form one large library from two smaller ones - essentially unpacking and then repacking as one. You use ar -x libfile.a to extract modules, and then you can use ar -a libfile2.a name1.o name2.o to add the object files into the new library.

However, I would just tell the users of your two components to link against both libraries. Much easier solution.