變量名占用多少字節？

Question

char fooishness = 'f';

存儲f需要 1 個字節，但存儲fooishness需要多少個字節？ 在哪里？ 它是如何擴展的？ 我讀過這個，但它沒有解決命名所需的空間。

如果我有一個字符數組，尋址數組是否需要比保存數據本身更多的存儲空間？

Answer 1

名稱對於 C++ 程序來說是短暫的：不管你如何命名事物，執行的代碼 [大部分] 保持不變。 很少有例外，名稱的性質實際上確實進入了程序的可觀察行為，例如，當使用std::type_info()時，它確實提供了對有點類似於類型名稱的實體的訪問。

雖然名稱不影響存儲的程序實體的大小，但無論它們是在堆上、堆棧上、全局 memory 還是嵌入在其他對象中的名稱都可能對程序本身產生大小影響：用於各種實體的名稱與經常（但不一定）影響程序運行大小的調試信息。 此外，外部引用實體的名稱可能最終被用於 linker 符號，尤其是在使用任何形式的共享對象時，以解決這些事物所指的內容。 然而，在所有這些情況下，名稱都是一個常數大小，以某種方式影響程序大小。

Answer 2

零。

例子：

#include <iostream>

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

編譯后的可執行文件61,376 字節

    #include <iostream>

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

編譯后的可執行文件61,376 字節