c++ - 未使用的全局变量的静态初始值设定项

Question

如果我有一个从未使用过的具有内部链接的全局，它的初始化程序是否保证运行？例如:

static int x = SideEffectfulFunction();

或

namespace {
    int x = SideEffectfulFunction();
}

SideEffectfulFunction() 是否保证被调用，即使 x 从未被引用？还是删除 x 是合法的？

Answer 1

是的，标准保证了这一点

静态存储时长[basic.stc.static]

2 If a variable with static storage duration has initialization or a destructor with side effects, it shall not be eliminated even if it appears to be unused, except that a class object or its copy/move may be eliminated as specified in 15.8.