堆内存分配崩溃与std :: wstring

size_t size;
mbstowcs_s(&size, NULL, 0, buffer, _TRUNCATE);
wchar_t *buffer2 = (wchar_t*)malloc(size + 1);
mbstowcs_s(&size, buffer, buffer_size, buffer, _TRUNCATE);
buffer2[size] = '';

std::wstring data(buffer);

std::wstring data(L"hello");

wchar_t *buffer2 = (wchar_t*)malloc((size + 1) * sizeof(wchar_t));
                                               ^^^^^^^^^^^^^^^^^

malloc

wchar_t

wchar_t *buffer2 = new wchar_t[size+1];