SUBEX pressions评估顺序 [英] subexpressions evaluation order

问题描述

我看了 SO / IEC 9899： 201X下J.1不确定的行为的：

"The order in which subexpressions are evaluated and the order in which side effects
take place, except as specified for the function-call (), &&, ||, ?:, and comma
operators (6.5)."

这是否意味着，在

Does this means that in

func1() + func2();

FUNC2（）而定）func1的（前pformed $ P $，甚至在func1的（）？

func2() may be preformed before func1(), or even during func1() ?

推荐答案

在当前的标准（ISO / IEC 9899：1999）有函数调用，但是操作数的计算顺序之间的序列点 + 没有指定这样 FUNC1 可称为前或后 FUNC2 但函数调用必须不重叠或以任何方式进行交织。

In the current standard (ISO/IEC 9899:1999) there is a sequence point between function calls but the order of evaluation of the operands to + is not specified so func1 may be called before or after func2 but the function calls must not overlap or be interleaved in any way.

这意味着，每个 FUNC1 和 FUNC2 可以，如果需要的话，有一些共享的数据交互，而具有以意想不到的方式下，其数据的变化。

This means that each of func1 and func2 can, if desired, interact with some shared data without having that data change under it in an unexpected way.

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