#include <iostream>
 
class DangerousString {
private:
    std::string data;
public:
    DangerousString(const std::string& str) : data(str) {
        std::cout << "DangerousString created: " << data << std::endl;
    }
 
    ~DangerousString() {
    	data = "";
        std::cout << "DangerousString destroyed: " << data << std::endl;
    }
 
    const char* getCStr() const {
        return data.c_str();
    }
};
 
void log(const char* str) {
    std::cout << "Log message: " << str << std::endl;
}
 
int main() {
    const char* danglingPtr = DangerousString("Hello, World!").getCStr(); // ❌ UB!
    std::cout << "Before log call" << std::endl;
    log(danglingPtr); // Висячий указатель передаётся в log()!
}
 

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