Inline functions versus preprocessor macros

How do inline functions differ from macros in C++?

Macros are text substitution by the preprocessor; inline functions are real, type-checked functions. A macro ignores types and scope, may evaluate an argument several times (so SQUARE(i++) misbehaves) and needs heavy bracketing to avoid precedence bugs; it is also invisible to the debugger. An inline function evaluates each argument once, respects types, scope and overloading, and inline is only a hint the compiler may ignore.