采用类型相关(type-punning),手段是采用联合体union,比如下面这种类型相关的用法是安全的: #include union X { int m; short s; }; int main
nkey; /* key length, w/terminating null and padding */ /* this odd type prevents type-punning
uint8_t slabs_clsid; //item所在的slabclass的id值 uint8_t nkey; //键长 /* this odd type prevents type-punning