evert@localhost ~/C++/allegro $ g++ units.cpp main.cpp `allegro-config --cflags --static` -o risk
units.cpp:15:2: warning: no newline at end of file
units.cpp: In member function 'void unit::is_selected()':
units.cpp:12: error: 'buffer' was not declared in this scope
main.h:7: warning: 'buffer' initialized and declared 'extern'
evert@localhost ~/C++/allegro $