Visual C++ :: Const Char Returned By Various Functions

What is the programmers responsibility with respect to const char * returned by various functions, like the C++ string class c_str() function which returns a const char * to an c style string array? In VC++ I cannot delete a const char * which holds a string literal. Take the following code for example:

Code:
void func() //a useless function with illustrative code {
string s1("abcd");
string s2("efgh");
const char * cc1 = s1.c_str(); //c_str() returns a const char * c style string pointer
s2.c_str(); //this returns a const char *, which must be allocated on the heap right?
delete cc1; //produces run time error in Release mode in VC++
}

The problem with the above code snip is that space is allocated on the heap (or so I believe) for the const char *'s returned by the 2 calls to c_str(). The delete attempt fails and there is no opportunity to delete the space allocated by const char * because its not assigned to anything (however I see c_str() used this way extensively)

So, if I cannot delete a const char *, how does the memory get recovered? Perhaps the string objects s1 and s2 themselves have pointers to the items on the heap made by c_str() calls and they get deleted by the destructors of s1 and s2 when the function ends?