| 0:2(9): preprocessor error: Redefinition of macro x | |
| 0:5(9): preprocessor error: Redefinition of macro abc | |
| 0:8(9): preprocessor error: Redefinition of macro foo | |
| 0:11(9): preprocessor error: Redefinition of macro bar | |
| 0:14(9): preprocessor error: Redefinition of macro biff | |
| 0:17(9): preprocessor error: Redefinition of macro oper | |