c by gary lui

Step 1: Preprocessing In this step, the C code is preprocessed. This involves removing any comments, replacing any preprocessor directives with their corresponding code, and including any header files. The preprocessed code is then passed to the compiler for further processing.

Step 2: Compilation During the compilation step, the preprocessed code is converted into assembly language. The compiler checks the code for syntax errors and performs various optimizations to generate efficient assembly code. If there are no syntax errors, the compiler generates an object file containing the assembly code.

Step 3: Assembly In the assembly step, the object file generated during compilation is converted into machine code. This step is performed by the assembler, which translates the assembly instructions into binary instructions that can be executed by the CPU. The resulting machine code is stored in an object file.

Step 4: Linking During the linking step, all the object files generated from the compilation and assembly steps are combined together to create an executable file. The linker resolves any references to external functions or variables, and ensures that all the necessary code and data are included in the final executable. The resulting executable file can be executed by the operating system.

Step 5: Execution After the linking step, the executable file is ready to be executed. The operating system loads the executable file into memory and starts executing it. The CPU interprets the machine code instructions and performs the necessary computations. The program may interact with the user or perform various tasks, depending on its functionality.

Overall, the process of compiling and executing a C program involves several steps, including preprocessing, compilation, assembly, linking, and execution. Each step plays a crucial role in converting the human-readable C code into machine code that can be executed by the CPU.