今天看见一段C代码，发现里面有@,有点蒙圈。

shuaniaun

各位坛友，截图是我今天偶然发现的外挂adc驱动，为什么联合体的后面有个@,看介绍是用来赋值的，不是说C里不能有@吗，还是新特性？

eric2013

C 2018放开了

ISO/IEC 9899:yyyy (open-std.org)

emwin

印象中C17是没有引入新特性的：

The current standard is ISO/IEC 9899:2018 (aka C17) -- this version addresses many defects reported for C11. It incorporates TCs (Technical Corrigenda) and does not introduce new language features. Sometimes mistakenly referred to as C18 because of the ISO publication date.