======== case 1 ========

MyClass::fun() is treated as inline funcion in both test70.cpp and test70a.cpp
--------------------
// test70.cpp
// cl /Ob1 /Fatest70.asm test70.cpp test70a.obj

#include "test70a.h"

void main()
{
    MyClass obj;
    obj.fun(10); // inline expanded
}
--------------------
// test70a.h

class MyClass
{
public:
    inline void fun(int x);     // at least one has specified inline
    void fun2();
};

inline void MyClass::fun(int x) // at least one has specified inline
{
    x = x + 1;
}
--------------------
// test70a.cpp
// cl /Ob1 /Fatest70a.asm /c test70a.cpp

#include "test70a.h"

void MyClass::fun2()
{
    fun(10); // inline expanded
}

======== case 2 ========

MyClass::fun() is treated as a regular funcion in test70.cpp 
and as a inline expanded function in test70a.cpp
in the link stage, fun() referenced in test70.cpp will be missing
--------------------
// test70.cpp
// cl /Ob1 /Fatest70.asm test70.cpp test70a.obj

#include "test70a.h"

void main()
{
    MyClass obj;
    obj.fun(10); // fun() is treated as a function call
}
--------------------
// test70a.h

class MyClass
{
public:
    inline void fun(int x); // at least one has specified inline
    void fun2();
};

--------------------
// test70a.cpp
// cl /Ob1 /Fatest70a.asm /c test70a.cpp

#include "test70a.h"

void MyClass::fun(int x)
{
    x = x + 1;
}

void MyClass::fun2()
{
    fun(10); // fun() is inline expanded
}

======== case 3 ========

MyClass::fun() is treated as a regular funcion in test70.cpp 
and as a inline expanded function in test70a.cpp
in the link stage, fun() referenced in test70.cpp will be missing
--------------------
// test70.cpp
// cl /Ob1 /Fatest70.asm test70.cpp test70a.obj

#include "test70a.h"

void main()
{
    MyClass obj;
    obj.fun(10); // fun() is treated as a function call
}
--------------------
// test70a.h

class MyClass
{
public:
    void fun(int x); // at least one has specified inline
    void fun2();
};

--------------------
// test70a.cpp
// cl /Ob1 /Fatest70a.asm /c test70a.cpp

#include "test70a.h"

inline void MyClass::fun(int x)
{
    x = x + 1;
}

void MyClass::fun2()
{
    fun(10); // fun() is inline expanded
}