libdispatch(apple-open-source)中的这段代码是什么意思?

what's meaning of this code from the libdispatch (apple-open-source)?

我很难理解以下代码:

struct dispatch_block_private_data_s {
    DISPATCH_BLOCK_PRIVATE_DATA_HEADER();
    static void* operator new(size_t) = delete;
    static void* operator new [] (size_t) = delete;
    explicit inline DISPATCH_ALWAYS_INLINE dispatch_block_private_data_s(
            dispatch_block_flags_t flags, voucher_t voucher,
            pthread_priority_t priority, dispatch_block_t block) noexcept :
            dbpd_magic(), dbpd_flags(flags), dbpd_atomic_flags(),
            dbpd_performed(), dbpd_priority(priority), dbpd_voucher(voucher),
            dbpd_block(block), dbpd_group(), dbpd_queue(), dbpd_thread()
    {
        // stack structure constructor, no releases on destruction
        _dispatch_block_private_data_debug("create, block: %p", dbpd_block);
    }
};

static void* operator new(size_t) = delete; 是什么,为什么 inlinestruct 中起作用?谁能帮我学习这些代码?这是 code address

注意 .cpp 扩展名。这是 C++ 代码。

  1. operator ... = delete 语法表明应该禁止使用此运算符,如果您尝试使用它会生成编译器警告。

  2. inline 限定符是一种性能优化。引用自The C++ Programming Language

    The inline specifier is a hint to the compiler that it should attempt to generate code for a call of [the function] inline rather than laying down the code for the function once and then calling through the usual function call mechanism.

    如果(a)一个函数很小;并且(b)性能是最重要的,您可以使用 inline 限定符,这样编译器将有效地在您使用函数的任何地方插入函数代码,而不是将其保存为函数并正常调用它将。这节省了调用函数的适度开销。

如果您在理解 C++ 方面需要帮助,我建议您查看 these resources