[] operator in std::map is giving me segmentation fault [closed]

问题

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Closed 7 years ago.

I have a

std::map<std::string, myClass*> myMap

then I am inserting like follow:

if(!myKey.empty())
{
    myMap[myKey] = this;
}

This sometime is throwing a segmentation fault.

Why??

回答1:

Maybe your myMap is no longer accessible. For instance, it might be a reference to a deleted pointer, or, much more probable, a member variable of an already deleted class:

class MyClass {
  public:
    selfInsert(std::string myKey) {
      if(!myKey.empty()) {
        myMap[myKey] = this;
      }
    }

  private:
    std::map<std::string, myClass*> myMap;
}

int main()
{
  MyClass *a = new MyClass();
  delete a;
  a->selfInsert();
}

来源：https://stackoverflow.com/questions/11252877/operator-in-stdmap-is-giving-me-segmentation-fault