c – 内存是否泄漏？

我在一个更大的代码中间有一小段代码：

int *p = new int[100];
p += 50;
delete []p;

编译器是否只删除第51个位置的内存？我认为确实如此.但是,在数组指针的情况下,编译器会保存一个附加项,该项指示已分配的对象数.那么,在这种情况下,是否应该继续删除超出分配大小的内存？
或者它是否删除第51个第100个元素并将第1个-50位保留在内存中,在这种情况下可能发生内存泄漏.

解决方法

这是未定义的行为. The C++ standard says：

3.7.4.2 Deallocation functions

3 … Otherwise,the behavior is undefined
if the value supplied to operator delete(void*) in the standard library is not one of the values returned
by a prevIoUs invocation of either operator new(std::size_t) or operator new(std::size_t,const
std::nothrow_t&) in the standard library,and the behavior is undefined if the value supplied to operator
delete[](void*) in the standard library is not one of the values returned by a prevIoUs invocation of
either operator new[](std::size_t) or operator new[](std::size_t,const std::nothrow_t&) in the
standard library.

4 … The effect of using an invalid pointer value (including passing it to a deallocation function) is undefined. (On some implementations,it causes a system-generated runtime fault.)