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Assigning a pointer after it is released

I am looking at the following code from Interviewing Programming:

bool deleteStack( Element **stack ){
      Element *next;
      while( *stack ){
            next = (*stack)->next;
            free( *stack );
            *stack = next;
      }
      return true;
}

I am not familiar with C ++ or C, so this might be a dumb question, but would not assign something to the pointer after release, will this cause a problem?

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4 answers

In your example *stack, this is a pointer. It is completely safe to free the memory that it points to, and then assign a pointer to a new variable.

The only thing that would be unsafe would be dereferencing *stackafter his release.

free( *stack );
next = (*stack)->next;

, , *stack, ( ) free.

+8

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, *stack. :

*stack = next;

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+4

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, , , , , ->, C/++, . , : stack->next : (*stack).next .

+1

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+1

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