Access to temporary object, C++ (clang)

Access to temporary object

//clang 3.8.0

#include <iostream>
#include <cstring>

struct A
{
    A(const char* data) { strcpy(this->data, data); std::cout << "A constructed" << std::endl; }
    A(const A& a) { strcpy(this->data, a.data); std::cout << "A copy-constructed" << std::endl; }
    ~A() { memset(data, '\0', sizeof(data)); std::cout << "A destroyed " << std::endl; }
    
    const char* c_str() { return data; } // return address of member
    
private:
    char data[100]; // some member
};

A return_A_by_value(const char* data)
{
    A a(data); // create A on stack
    const char* memberData = a.c_str();
    std::cout << "Here we can refer to objects's data since 'a' exists at this time: " << memberData << std::endl;
    return a; // temporary object is returned
}

int main()
{
    const char* data = return_A_by_value("[some text]").c_str(); // at the end of this line A will be destroyed
    
    try
    {
        // Dereferencing data can lead to undefined behavior 
        // since it is pointed to data member of destroyed object
        std::cout << "Here data is not valid pointer: <" << data << ">" << std::endl;
    }
    catch(const std::exception& e)
    {
        std::cout << e.what() << std::endl;
    }
}


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