-Oi: Inline Functions

Use the inline keyword or the command line option -Oi for C/C++ functions (see -Oi: Inlining for more information). Defining a function before using it helps the Compiler to inline it:

  /* OK */                       /* better! */

  
  void myfun(void);                void myfun(void) {

  
  void main(void) {                // ...

  
     myfun();                      }

  
  }                              void main(void) {

  
  void myfun(void) {                    myfun();

  
    // ...                       }

  
  }

  

This also allows the compiler to use a relative branch instruction instead of an absolute branch instruction.