When should I use __forceinline instead of inline?

Question

Visual Studio includes support for __forceinline. The Microsoft Visual Studio 2005 documentation states:

The __forceinline keyword overrides the co

Answer 1

When you know that the function is going to be called in one place several times for a complicated calculation, then it is a good idea to use __forceinline. For instance, a matrix multiplication for animation may need to be called so many times that the calls to the function will start to be noticed by your profiler. As said by the others, the compiler can't really know about that, especially in a dynamic situation where the execution of the code is unknown at compile time.