I have been testing inline function calls in C++.
Thread model: win32
gcc version 4.3.3 (4.3.3-tdm-1 mingw32)
Stroustrup in The C++ Program
There is no generic C++ way to FORCE the compiler to create inline functions. Note the word 'hint' in the text you quoted - the compiler is not obliged to listen to you.
If you really, absolutely have to make something be in-line, you'll need a compiler specific keyword, OR you'll need to use macros instead of functions.
EDIT: njsf gives the proper gcc keyword in his response.