Discuss the effects occur, after an exception thrown by a member function is unspecified by an exception specification. | C++

When a function throws an exception, not given in the specification, the exception is passed to a system function named unexpected. The unexpected function calls the latest function named as an argument in a call to the set_unexpected function, which returns its current settings. A function with no exception specification, by default, calls the terminate function, which finally calls the abort (function to terminate the program).