c++ - 指向具有 vector 内存泄漏的对象的指针

Question

我似乎对 vector 有一点内存泄漏问题。我的代码如下所示:

    class CPart {
    public:
        virtual void print() = 0;
    };

    //some other classes

    class CDisk : public CPart {
    public:
        CDisk(int tp, int size);
        ~CDisk();
        virtual void print();
        void AddPartition(int size, const string & dsc);

        static const int MAGNETIC = 0;
        static const int SDD = 1;
    private:

        struct CPartition {
            CPartition(int size, const string & dsc);
            int div_size;
            string disk;
        };
        int type;
        int d_size;
        vector<CPartition> ptts;
    };

    CDisk::CDisk(int tp, int size) {
        type = tp;
        d_size = size;
    }

    CDisk::CPartition::CPartition(int size, const string& dsc) {
        div_size = size;
        disk = dsc;
    }

    void CDisk::AddPartition(int size, const string& dsc) {
        ptts.push_back(CPartition(size, dsc));
    }

    int main(int argc, char** argv) {
        CDisk disk(CDisk::SDD, 5000);
        disk.AddPartition(500, "disk1");
        CPart *disk2 = new CDisk(disk);
        delete disk2;
        return 0;
    }

当我用 valgrind 运行这段代码时，它说存在内存泄漏，丢失的字节数等于 vector ptts 中的项目数 * CPartition 的大小。所以我猜我必须以某种方式清理那个 vector 。我已经尝试过了，但无济于事。

Answer 1

你需要有 virutal destructor在C部分

 class CPart {
    public:
        virtual void print() = 0;
        virtual ~CPart(){};
    };

否则会出现以下情况；

  int main(int argc, char** argv) {
        CDisk disk(CDisk::SDD, 5000);
        disk.AddPartition(500, "disk1");
        CPart *disk2 = new CDisk(disk);//CDisk created
        delete disk2;//But here only CPart is deleted leaving CDisks data in memory
        return 0;
    }