5: STAGES OF C++

Stages of C++

1. Preprocessing

2. Compilation

3. Assembly

4. Linking Execution

Preprocessing

Compilation

Assembly

Linking Execution

Stages of C++

Preprocessing

• Handles all preprocessor directives (line starting with #, e.g., @#include, #define

• Expands macros, removes comments, and includes header files

• Output: a pure C++ source file (no directives, everything expanded)

Preprocessing

Output: a pure C++ source file (no directives, everything expanded)

Pure C++ Source File

Output of the Preprocessing Stage

Compilation

• The ___ translates the preprocessed source code into assembly language (human readable low-level code specific to the CPU

• Checks for syntax errors and converts high-level C++ constructs into lower level instructions

• Output: Assembly Code

Compilation

Output: Assembly Code

Assembly Code

The output of the Compilation stage

Assembly

• The ___ converts the ___ code into object code

  • e.g.) machine code, binary format, but not yet executable

• This is stored in an object file (.o or .obj)

• Contains: machine instructions, symbol table (function/variable references not yet linked

Assembly

• Contains: machine instructions, symbol table (function/variable references not yet linked

Assembly

Converts ___ code to object code

Linking

• The ___ combines object files and required libraries like <iostream>

• Resolves external references like cout, cin, or functions defines in other files

• Produces a final executable file (.exe, no extention, or .out)

Linking

• Produces a final executable file (.exe, no extention, or .out)

Executable File

Output of the Linking Stage

Execution

• The ___ file is loaded into memory by the operating system

• The CPU executes the machine instructions

• Program runs and produces output