1. Using an undefined member in any way other than as the target of an assignment is an error. 除了作为赋值的目标之外,以任何方式使用一个未定义的成员都是错误的。
2. The environment variable(s) specified in the debugging information file path are undefined. 没有定义在调试信息文件路径中指定的环境变量。
3. Floating to Floating conversions are defined only if N is representable; if it is not, the conversion has undefined behavior. 浮点数到浮点数的转换仅当N是可表示时有定义;否则转换就是未定义行为。
英英解释
adj.
1. not precisely limited, determined, or distinguished