vc6 include guiddef.h出错~~~

[powfulhongpowfulhong]

今天五一，不知有没有人在~~~先祝五一happy~~~~
在vs20008中include guiddef.h文件，能顺利编译执行，但在vc6中include 却出现下面的错误
guiddef.h(160) : error C2084: function 'int __cdecl IsEqualGUID(const struct _GUID &,const struct _GUID &)' already has a body
guiddef.h(160) : error C2732: linkage specification contradicts earlier specification for 'IsEqualGUID'
guiddef.h(159) : see declaration of 'IsEqualGUID'
guiddef.h(193) : error C2084: function 'int __cdecl operator ==(const struct _GUID &,const struct _GUID &)' already has a body
guiddef.h(193) : error C2732: linkage specification contradicts earlier specification for '=='
guiddef.h(192) : see declaration of '=='
guiddef.h(198) : error C2084: function 'int __cdecl operator !=(const struct _GUID &,const struct _GUID &)' already has a body
guiddef.h(198) : error C2732: linkage specification contradicts earlier specification for '!='
guiddef.h(197) : see declaration of '!='
guiddef.h(199) : error C2264: '==' : error in function definition or declaration; function not called
guiddef.h(199) : error C2088: '==' : illegal for struct

这是什么回事啊？