vc数据库，老出错，什么原因??

enum RecordCreateOptionsEnum
{
    adCreateCollection = 8192,
    adCreateStructDoc = -2147483648,//这行有问题
    adCreateNonCollection = 0,
    adOpenIfExists = 33554432,
    adCreateOverwrite = 67108864,
    adFailIfNotExists = -1
};

c:\documents and settings\administrator\桌面\examonline\debug\msado15.tlh(407) : warning C4146: unary minus operator applied to unsigned type, re