你能在 C++ 中混合使用 free 和构造函数吗？
我正在阅读这个问题：
在什么情况下使用 malloc 与 new？
有人提出使用 malloc 的原因之一是如果您要使用 free。
我想知道：在 C++ 中混合自由调用和构造函数初始化是否有效？
即
我可以说：
my_type *ptr = new my_type;
free(my_type);
这是否在某种程度上无效或更糟糕
my_type *ptr = new my_type;
delete my_type;
除了它不是 c++ 的事实之外，
？同样，你能做相反的事吗？你能说，
my_type *ptr = (my_type *)malloc(sizeof(my_type));
delete my_type;
如果这是重复的，请合并，我搜索过，但没有看到关于 malloc/delete/new/free 的问题。
Possible Duplicate:
Is there any danger in calling free() or delete instead of delete[]?
I was reading this question:
In what cases do I use malloc vs new?
Someone raised that one reason to use malloc was if you were going to use free.
I was wondering: Is it valid to mix a free call and a constructor initialization in C++?
i.e.
Can I say:
my_type *ptr = new my_type;
free(my_type);
Is that somehow invalid or worse than:
my_type *ptr = new my_type;
delete my_type;
other than the fact that it's not c++ish?
Likewise, could you do the opposite? Can you say
my_type *ptr = (my_type *)malloc(sizeof(my_type));
delete my_type;
Please merge if this is a duplicate, I searched but didn't see a question along this lines exactly about malloc/delete/new/free asked.
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不，它是无效的。不保证
new将使用malloc或delete将使用free。此外，使用
free而不是delete将跳过my_type的析构函数。如果my_type本身持有一些资源，这些资源将会被泄漏。同样，malloc 将跳过构造函数，因此变量可能处于无效状态。No it is invalid. There is no guarantee that
newwill usemallocordeletewill usefree.Moreover, using
freeinstead ofdeletewill skipmy_type's destructor. Ifmy_typeitself is holding some resources, those will be leaked. Similarly,mallocwill skip the constructor so the variable may be in an invalid state.不，不是。
malloc、calloc、realloc ->免费
新->删除
新的[]->删除[]
No it is not.
malloc,calloc,realloc -> free
new -> delete
new[] -> delete[]
不，这是无效的。
malloc（和其他 C 分配函数）必须与free匹配，new必须与delete匹配，并且new []必须与delete []匹配。虽然如果没有析构函数代码，您的编译器不一定会执行任何不同的操作，但这不是您应该依赖的东西。主要区别在于new/delete调用对象的构造函数和析构函数； malloc 和 free 只是将其视为原始的、无类型的内存。
No, this is not valid.
malloc(and other C allocation functions) must be matched withfree,newmust be matched withdelete, andnew []must be matched withdelete []. While your compiler may not necessarily do anything differently if there is no destructor code, this is not something you should rely on.The main difference is that new/delete call the constructor and destructor of an object; malloc and free just treat it as raw, untyped memory.
free()不调用析构函数。它只是释放内存，不问任何问题。new/delete不保证使用malloc()作为其内存分配器；free甚至可能不知道你扔给它的内存free()does not call the destructor. It just deallocates the memory, no questions asked.new/deleteis not guaranteed to usemalloc()as its memory allocator;freemight not even know about the memory you're throwing at it