Compiler

Compilation process of a C program

Executable creation

• PREPROCESSING

  • Removal of comments

  • Interpretation of preprocessor directives (#)

• COMPILING

  • Translation of source code into assembly language

• ASSEMBLING

  • Creation of object code

• LINKING

  • Combining with system libraries and/or libraries from other files

Extensions recognized

File Type	Extension
Header file	.h
Source file	.c
Preprocessed source file	.i
Assembly file	.s
Object module	.o
Dynamic libraries	.so
Static libraries	.a

GCC (GNU Compiler Collection)

A project by the Free Software Foundation, an organization founded by Richard M. Stallman as a protest against proprietary software licenses.

Multi-target compiler for:

• C (originally created for this language)

• Java, C++, Objective-C, Fortran, and Ada (front-end support)

• Various machine languages (back-end support)

gcc [OPTIONS] source_file

Option	Description
-Wall	Sets the highest warning level
-w	Suppresses all warning messages
-g	Generates information useful for DEBUGGING
-o fileOutput	Specifies the output file of the compilation
-E	Stops the process after the preprocessing phase (Does NOT perform COMPILATION)
-S	Stops the process after the compilation phase (Does NOT perform ASSEMBLY)
-c	Compiles and/or assembles the source after preprocessing (Does NOT perform linking with libraries)
-pedantic	Informs the programmer when deviating from the ISO standard
-O	Enables optimization of the executable file
-std=cXX	Specifies the C standard to use (by number XX)
-std=c++XX	Specifies the C++ standard to use (by number XX)
-Ldirectory -lname_library	-L specifies the directory to search for library files (static or dynamic) -l indicates the library name to use

Analysis of a binary file

objdump  [OPTIONS]  binary_file

Option	Description
--disassemble -Dslx -d	Disassemble the binary file
-h	View ELF headers
-full-contents	View an ELF section