Designing a game loop.

I'm developing a simple Win game. Here is my 2 similar implementations of the game loop (in c++):

approach #1:

Code:

---

    while (Msg.message != WM_QUIT) {
   
                    if (PeekMessage(&Msg, NULL, 0, 0, PM_REMOVE) > 0) {
                            TranslateMessage(&Msg);
                            DispatchMessage(&Msg);
                    }
                    else {
                // Do update, rendering and all the real game loop stuff
            }
    }

---

approach #2:

Code:

---

    while (Msg.message != WM_QUIT) {
   
                    if (PeekMessage(&Msg, NULL, 0, 0, PM_REMOVE) > 0) {
                            TranslateMessage(&Msg);
                            DispatchMessage(&Msg);
                    }
                   
            // Do update, rendering and all the real game loop stuff
           
    }}

---

My question is which one is better and which one should i choose? Is it better to do the update and rendering stuff in the else closure as in the #1 approach or just in the `while` loop block as in the #2 approach?

Neither of those would work. You've coded a message pump. Ideally, you'd be using different threads, but typically you'd call your message pump from inside a tight loop elsewhere in the program rather than calling your other code from inside the message pump.