client.c:996: error: a label can only be part of a statement and a declaration is not a statement

switch(a){
case 1:
....................
....................
....................
break;
case 2:
break;
}
　
在GCC下编译会出现如下错误：
error: a label can only be part of a statement and a declaration is not a statement
但加上如下括号后，就没有错误了，这是为什么？编译器的问题？
switch(a){
case 1:
｛
....................
....................
....................
｝
break;
case 2:
break;
}
http://zhidao.baidu.com/link?url=fSrpX7VaVXd5-L8c2zj2xVDSbh8bM-5xyO6iyZOYgV30mI_iZlASQmNakmGSC-4gnPO3oG2HzIAvdSVayOTjTa
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