Compile C++ using GCC

GCC (shorthand for 'GNU Compiler Collection') is a collection of compilers able to compile multiple different programming languages.

This page describes how to compile C++ code using the GCC.

Procedure

0. Create a C++ source file

You will need C++ code to work on.

In this optional step, a file with a minimal C++ program is created.

Create and write a C++ source file called hello_world.cpp:

nano hello_world.c

In nano, write the C++ program as such:

#include <iostream>

int main()
{
  std::cout << "hello, world\n";
}

1. Load a GCC module

Load a recent GCC module:

module load gcc/13.2.0

Do I really need to load a module?

No, as there is a system-installed GCC.

For sake of doing reproducible research, always load a module of a specific version.

2. Compile the source file

After saving and closing nano, compile as such:

g++ hello_world.cpp

This compiles the file hello_world.cpp using all defaults:

• default/no optimization
• the executable created is called a.out

To compiles the file hello_world.cpp with run-time speed optimization and creating an executable with a more sensible name, use:

g++ -O3 -o hello_world hello_world.cpp

• -O3: optimize for run-time speed
• -o hello_world: the executable created is called hello_world

3. Run

Run the program:

./a.out 

Output:

hello, world