When debugging optimized C++ in Visual Studio you'll run into the same problem. The 'see ASM' feature is easy enough to use that it helps, but, there's no free lunch.

Probably the compiler should both inline it and include a standalone version when debugging is enabled.

No, because you need to debug the code you're actually running, not some other code that's easier to debug.

I believe we're talking about a function such as std::vector::operator[]. You wouldn't usually be debugging a particular attempt to access an element of a vector, you'd have a vector and want to easily see what's in it, using a debugger-constructed call to the function.