Static compilation Link

Static links include Address and space allocation, symbolic resolution, and relocation.

Different modules are compiled as different target files. There are two types of communication in different target files: function calls between modules and variable access between modules.

To access a function, you need to know the address of the target function. to access a variable, you also need to know the address of the target variable. These addresses cannot be obtained during compilation. the compiler will temporarily ignore these addresses, the process of determining these addresses is called relocation. Each location to be relocated is called the relocation entry.