Problem when calling a function when it is in .lib

Question

I have a class with a static method that looks something like this:

class X {
    static float getFloat(MyBase& obj) {
        return obj.value();  // MyBase::value() is virtual
    }
};

I call it with an instance of MyDerived, which subclasses MyBase:

MyDerived d;
float f = X::getFloat(d);

If I link the obj file containing X to my executable, everything works as expected. If I expect to get 3.14, I get it.

If I create a .lib containing an X.obj file and a link in .lib, it breaks. When I call getFloat (), it returns -1. # IND00 . Is this some kind of sentinel value that should tell me what's wrong here?

Is there anything else when you directly link in lib and not obj?

I do not get any warnings or compiler errors.

Edit:
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Answer 1

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Answer 2

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Answer 3

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If you use visual studio instead of explicitly specifying the .lib file, simply right-click on the project and install the dependencies on the .lib project. This way you will make sure that it is using the correct .lib file.