diff --git a/debug.h b/debug.h
--- a/debug.h
+++ b/debug.h
@@ -19,9 +19,6 @@
 	extern int _debug_oldloader_level;
 	extern int _debug_pbs_level;
 	extern int _debug_ntp_level;
-#ifdef GPMI
-	extern int _debug_gpmi_level;
-#endif /* GPMI */
 	extern int _debug_npf_level;
 #endif
 
@@ -30,8 +27,4 @@ void CDECL debug(const char *s, ...);
 void SetDebugString(const char *s);
 const char *GetDebugString(void);
 
-#ifdef GPMI
-void gpmi_debug_openttd(int level, char *s);
-#endif /* GPMI */
-
 #endif /* DEBUG_H */