This option forces all inline functions to be treated as if they are qualified with __forceinline.

Inline functions are functions that are qualified with inline or __inline. In C++, inline functions are functions that are defined inside a struct, class, or union definition.

If you use --forceinline, the compiler always attempts to inline those functions, if possible. However, it does not inline a function if doing so causes problems. For example, a recursive function is inlined into itself only once.

__forceinline behaves like __inline except that the compiler tries harder to do the inlining.