c++ - .cpp 文件中类型相同但主体不同的内联函数

Question

有点奇怪，不太实用，但我正在 cpp 中使用内联尝试一些随机的东西，我考虑尝试一下:

 inline void foo(void){static int x=0; x++; cout << x << '\n'; return;};

在另一个 .cpp 文件中我有:

 inline void foo(void){static int x=0; x=x+2; cout << x << '\n'; return;};

现在，由于某种原因(相同的函数类型/名称)，但主体不同，它们都共享相同的 'x' 但它们的定义不同。我希望编译器会提示，但事实并非如此。这是为什么？

Answer 1

根据basic.def.odr#13，该程序格式不正确，无需诊断 :

13. There can be more than one definition of a

• inline function or variable ([dcl.inline]),

in a program provided that each definition appears in a different translation unit and the definitions satisfy the following requirements.Given such an entity D defined in more than one translation unit, for all definitions of D, or, if D is an unnamed enumeration, for all definitions of D that are reachable at any given program point, the following requirements shall be satisfied.

• Each such definition shall consist of the same sequence of tokens, where the definition of a closure type is considered to consist of the sequence of tokens of the corresponding lambda-expression.

15. If these definitions do not satisfy these requirements, then the program is ill-formed; a diagnostic is required only if the entity is attached to a named module and a prior definition is reachable at the point where a later definition occurs.

(强调我的)

由于示例中的函数定义不包含相同的标记序列，因此该程序格式不正确，无需诊断。