The std line should crash but not

Question

I have a class:

class A {
  public:
  string B;
};

and then the code:

A a1;
a1.B = "abc";

printf("%p.\n", a1.B.c_str());

A a2(a1);

printf("%p.\n", a2.B.c_str());

The c_str of both instances refer to the same place (as I understand it, the copied constructor is copied and the string internally stores data in char *, and the pointer is copied.

but the question is why is this code not crashing? a1 and a2 are stack variables, when deconstructing them, line B will also be deconstructing, will the internal char * from these lines (which points to the same memory location) be deleted twice? Isn't that a double deletion that should cause a crash? btw I disabled gcc optimizations, and valgrind doesn't show anything either.

Answer 1

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