C Program Compilation Steps

The compilation process of a C program involves several stages, from the source code written in the hello.c file to the creation of an executable file that can be loaded and executed by the operating system. Here is a simplified overview of the compilation process:

Source Code (hello.c):

The process begins with a programmer writing the source code in the C programming language. The source code is usually saved in a file with a .c extension, such as hello.c.

Preprocessing:

The preprocessor (cpp) is the first stage of compilation. It handles directives, such as #include and #define, and expands them. The result is a modified version of the source code, often referred to as the "preprocessed code."

Compilation:

The compiler (gcc) takes the preprocessed code and translates it into assembly code specific to the target platform. The output is stored in an assembly code file.

Assembly:

The assembler (as) takes the assembly code and converts it into machine code in the form of relocatable object files. These files typically have a .o or .obj extension.

Linking:

The linker (ld) combines the object files generated in the previous step with other necessary files (such as libraries) to create an executable file. It resolves symbols, assigns memory addresses, and generates the final executable.

Loader:

The loader is part of the operating system and is responsible for loading the executable file into memory for execution. It resolves addresses and sets up the runtime environment for the program.

This sequence of steps, from source code to loader, is a simplified representation of the C compilation process. Modern compilers, like GCC, often handle many details automatically, and additional tools may be involved for optimization and debugging. The resulting executable file (hello in this case) can then be executed to run the C program.