Is it safe to `delete this`? [duplicate]

by

delete this is legal and does what you would expect: it calls your class’s destructor and free the underlying memory. After delete this returns, your this pointer value does not change, so it is now a dangling pointer that should not be dereferenced. That includes implicit dereferencing using the class’s member variables.

It is usually found in reference-counted classes that, when the ref-count is decremented to 0, the DecrementRefCount()/Release()/whatever member function calls delete this.

delete this is typically considered very bad form for many reasons. It is easy to accidentally access member variables after delete this. Caller code might not realize your object has self-destructed.

Also, delete this is a “code smell” that your code might not have a symmetric strategy for object ownership (who allocates and who deletes). An object could not have allocated itself with new, so calling delete this means that class A is allocating an object, but class B is later freeing it[self].

More Related Contents:

  1. Is “delete this” allowed in C++?
  2. Double free or corruption after queue::push
  3. Modifying a char *const string
  4. Should “delete this” be called from within a member method?
  5. Should objects delete themselves in C++?
  6. What’s the difference between 'gcc -g' and 'gcc -g3'?
  7. How do I flush the cin buffer?
  8. Why do function pointer definitions work with any number of ampersands ‘&’ or asterisks ‘*’?
  9. Create N-element constexpr array in C++11
  10. How to link C++ program with Boost using CMake
  11. Virtual functions and performance – C++
  12. How to explain undefined behavior to know-it-all newbies?
  13. How to compile Qt 5 under Windows or Linux, 32 or 64 bit, static or dynamic on Visual Studio or g++
  14. What is the point of noreturn?
  15. Array initialization use const variable in C++
  16. Is storing an invalid pointer automatically undefined behavior?
  17. Should I include or in C++ programs?
  18. “The system cannot find the file specified” when running C++ program
  19. Convert std::tuple to std::array C++11
  20. Class template argument deduction not working with alias template
  21. Error: variable “cannot be implicitly captured because no default capture mode has been specified”
  22. What is the Fastest Method for High Performance Sequential File I/O in C++?
  23. difference between global operator and member operator
  24. When do extra parentheses have an effect, other than on operator precedence?
  25. Why is memset() incorrectly initializing int?
  26. dynamically allocated memory after program termination
  27. Static global variables in C++
  28. CMake and MsVS-NuGet
  29. How does calling srand more than once affect the quality of randomness?
  30. Why is there no multiple definition error when you define a class in a header file?

Leave a Comment