C program compilation process
Compilation refers to the process of converting source code into object code, which is completed by compiler.
- Removal of Comments
- Expansion of Macros
- Expansion of the included files
- Conditional compilation
Convert high-level code(C language) into assembly language.
Convert assembly language into machine language.
Make code of functions which are in the library and other object files available to your main program.
Static Linking —— (.a, .lib)
Copy the code of function from other files to your object code before load.
- Speed: faster
- Space: larger
- When publishing the program, we don't need to consider whether the library files exist in the user's computer.
Dynamic Linking ——(.so, .dll)
Get the address of the function, and load the code of function at run-time. (like a pointer)
- Speed: slower
- Space: smaller
- When publishing the program, we need to consider whether the library files exist in the user's computer and whether the version is up to date.
- More independent, suitable for large-scale software development