diff --git a/core/planner.c b/core/planner.c
index 598e568bf..a4c93ba77 100644
--- a/core/planner.c
+++ b/core/planner.c
@@ -92,7 +92,7 @@ int get_cylinderid_at_time(struct dive *dive, struct divecomputer *dc, duration_
 	return cylinder_idx;
 }
 
-int get_gasidx(struct dive *dive, struct gasmix mix)
+static int get_gasidx(struct dive *dive, struct gasmix mix)
 {
 	return find_best_gasmix_match(mix, &dive->cylinders);
 }
diff --git a/core/planner.h b/core/planner.h
index 6d0353db0..48d2bb33f 100644
--- a/core/planner.h
+++ b/core/planner.h
@@ -42,22 +42,13 @@ extern "C" {
 
 extern int validate_gas(const char *text, struct gasmix *gas);
 extern int validate_po2(const char *text, int *mbar_po2);
-extern timestamp_t current_time_notz(void);
-extern void set_last_stop(bool last_stop_6m);
-extern void set_verbatim(bool verbatim);
-extern void set_display_runtime(bool display);
-extern void set_display_duration(bool display);
-extern void set_display_transitions(bool display);
 extern int get_cylinderid_at_time(struct dive *dive, struct divecomputer *dc, duration_t time);
-extern int get_gasidx(struct dive *dive, struct gasmix mix);
 extern bool diveplan_empty(struct diveplan *diveplan);
 extern void add_plan_to_notes(struct diveplan *diveplan, struct dive *dive, bool show_disclaimer, int error);
 extern const char *get_planner_disclaimer();
 extern char *get_planner_disclaimer_formatted();
 
 extern void free_dps(struct diveplan *diveplan);
-extern struct dive *planned_dive;
-extern char *cache_data;
 
 struct divedatapoint *plan_add_segment(struct diveplan *diveplan, int duration, int depth, int cylinderid, int po2, bool entered, enum divemode_t divemode);
 struct divedatapoint *create_dp(int time_incr, int depth, int cylinderid, int po2);