c-defun-tactic is a variable defined in `cc-vars.el'.
Its value is

*Whether functions are recognized inside, e.g., a class.
This is used by `c-beginning-of-defun' and like functions.

Its value is one of:
t -- Functions are recognized only at the top level.
go-outward -- Nested functions are also recognized. Should a function
command hit the beginning/end of a nested scope, it will
carry on at the less nested level.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 24.1 of Emacs.