I presume you're aware that you've chosen two controversial examples? "register" has been formally deprecated in C++, and has been ignored by (almost?) all C compilers for decades: http://stackoverflow.com/questions/20618008/replacement-for-...

And most current wisdom is that "inline" no longer serves as a useful performance suggestion to the compiler, but instead should only be used as a linkage directive to allow multiple declarations of the same function: http://stackoverflow.com/questions/29796264/is-there-still-a...