Runtime Stack and Recursion

• Runtime environment (Ada, C, C++, Java, Pascal ...)
• Contiguous address space allocated by OS
• [static | stack -->      ...      <-- heap]
• static: executable codes, symbol table, global variables
• stack: push/pop for every function call/return
• Current active call at top of stack
• heap: new/delete dynamic memory
• If stack and heap collide then program crashes
• stack = stack < AR > // AR = Activation Record
• Function name and code location (in static)
• Function parameters
• Function return value
• Control return location
• Recursion
• Order 1: function calls itself
• Order 2: F() calls G(), G() calls F()
• Facilitated by stack