Suggestion:
PsychadelicGumballMachine, start troubleshooting from the basics. Create and run a brand new test C project. After confirming that it compiles and run, in the 'helloWorld' code that was created automatically insert the #define and recompile. The issue should not occur, which makes the environment or particularly the affected project the prime suspect. The issue you report is not reproducible
To cover every angle, in case the basic 'helloWorld' code does have the issue when you add the #define, then please follow previous advise and provide the requested logs to the original thread. Opening a new thread with the same question is not right, a breach of protocol; lesson learned we hope.