c++ - sizeof(function) 有意义吗？

Question

我对 sizeof(function) 有点困惑。我曾经认为 sizeof 运算符对类对象、指针和引用进行操作。

sizeof 运算符可以操作哪些操作数？

sizeof(function) 有意义吗？

Answer 1

根据:http://en.cppreference.com/w/cpp/language/sizeof

"...sizeof cannot be used with function types, incomplete types, or bit-field glvalues"

或来自 2012 年 C++ 标准工作草案 http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3337.pdf :

Section 5.3.3 Sizeof "The sizeof operator shall not be applied to an expression that has function or incomplete type, to an enumeration type whose underlying type is not fixed before all its enumerators have been declared, to the parenthesized name of such types, or to an lvalue that designates a bit-field."