Install unifdef by entering the following commands in the terminal:
sudo apt update sudo apt install unifdef
Description:
Remove cpp '#ifdef' lines from files
The unifdef utility selectively processes conditional cpp(1) directives. It removes from a file both the directives and any additional text that they specify should be removed, while otherwise leaving the file alone.
Homepage: http://dotat.at/prog/unifdef/
Version: 2.10-1.1
Section: universe/devel