std::shared_ptr 意外地更改其底层指针，尽管它是常量

Question

我尝试运行这段代码：

//find() should return a std::optional<std::reference_wrapper<std::shared_ptr<pieces>>>
//pieces is an abstract class
const auto find_result = array_of_shared_ptr_wrapper.find(target) ;
//ensure find_result has value... 
const auto& piece_at_target = find_result.value().get();
std::cout << piece_at_target.use_count() << std::endl; 
//Print 2 as expected, using a debugger the pointer still point to the 
//same address as the pointer in the array, the data inside is still correct. 
std::cout << piece_at_target.use_count() << std::endl;
//Print random garbage, piece_at_target underlying pointer is changed, now different 
//from the one in the array, the data inside is messed up. 

所以我的问题是这怎么会发生？任何避免此问题的方法，因为我试图将

piece_at_target

设置为

nullptr

并且出现分段错误。在使用调试器进行调查后，代码似乎试图删除指向随机垃圾的指针，这导致了错误。