c++ - 构造函数参数的求值顺序

Question

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Answer 1

这是一个 bug in GCC (感谢 Casey 的链接)。您引用的段落通常适用于列表初始化，其中术语在第 8.5.4/1 段中定义得非常清楚:

List-initialization is initialization of an object or reference from a braced-init-list. Such an initializer is called an initializer list, and the comma-separated initializer-clauses of the list are called the elements of the initializer list.

没有理由相信这只适用于初始化列表构造函数的调用。此外，您引用的段落中的说明澄清了:

This evaluation ordering holds regardless of the semantics of the initialization; for example, it applies when the elements of the initializer-list are interpreted as arguments of a constructor call, even though ordinarily there are no sequencing constraints on the arguments of a call.