变量名占用多少字节？

Question

char fooishness = 'f';

存储f需要 1 个字节，但存储fooishness需要多少个字节？ 在哪里？ 它是如何扩展的？ 我读过这个，但它没有解决命名所需的空间。

如果我有一个字符数组，寻址数组是否需要比保存数据本身更多的存储空间？

Answer 1

名称对于 C++ 程序来说是短暂的：不管你如何命名事物，执行的代码 [大部分] 保持不变。 很少有例外，名称的性质实际上确实进入了程序的可观察行为，例如，当使用std::type_info()时，它确实提供了对有点类似于类型名称的实体的访问。

虽然名称不影响存储的程序实体的大小，但无论它们是在堆上、堆栈上、全局 memory 还是嵌入在其他对象中的名称都可能对程序本身产生大小影响：用于各种实体的名称与经常（但不一定）影响程序运行大小的调试信息。 此外，外部引用实体的名称可能最终被用于 linker 符号，尤其是在使用任何形式的共享对象时，以解决这些事物所指的内容。 然而，在所有这些情况下，名称都是一个常数大小，以某种方式影响程序大小。

Answer 2

零。

例子：

#include <iostream>

int main() {
    char fooishness = 'f';
    std::cout << fooishness << std::endl;
    return 0;
}

编译后的可执行文件61,376 字节

    #include <iostream>

int main() {
    char fooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishness = 'f';
    std::cout << fooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishnessfooishness << std::endl;
    return 0;
}

编译后的可执行文件61,376 字节