diff --git a/sw/simulator/Makefile b/sw/simulator/Makefile
index 91d632c21f..2bc8848034 100644
--- a/sw/simulator/Makefile
+++ b/sw/simulator/Makefile
@@ -43,8 +43,7 @@ SIMSA=sims.cma
 OCAMLC = ocamlc
 OCAMLOPT=ocamlopt -p
 INCLUDES= -I +lablgtk2 -I ../lib/ocaml
-# OCAMLCC = gcc -Werror -O2 -I /usr/include/glib-2.0 -I /usr/lib/glib-2.0/include -DSITL -DUBX -DMOBILE_CAM -DAP -DDOWNLINK -DINFRARED -DGPS -I $(OBJDIR) -I $(ACDIR) 
-OCAMLCC = gcc -Werror -O2 -I /usr/include/glib-2.0 -I /usr/lib/glib-2.0/include -DSITL $(ap.CFLAGS) -I $(OBJDIR) -I $(ACDIR) 
+OCAMLCC = gcc -Werror -W -Wall -O2 -I /usr/include/glib-2.0 -I /usr/lib/glib-2.0/include -DSITL $(ap.CFLAGS) -I $(OBJDIR) -I $(ACDIR) 
 
 AIRBORNE = ../airborne
 VARINCLUDE=$(PAPARAZZI_HOME)/var/include
diff --git a/sw/simulator/sim_ap.c b/sw/simulator/sim_ap.c
index a57d050b56..e0d7f0b0d4 100644
--- a/sw/simulator/sim_ap.c
+++ b/sw/simulator/sim_ap.c
@@ -14,6 +14,8 @@
 #include "flight_plan.h"
 #include "nav.h"
 #include "pid.h"
+#include "infrared.h"
+#include "cam.h"
 
 #include <caml/mlvalues.h>
 #include <caml/memory.h>
@@ -35,7 +37,7 @@ static int16_t values_from_ap[RADIO_CTL_NB];
 
 uint16_t ppm_pulses[ PPM_NB_PULSES ]; /** From ppm_hw.c */
 
-value sim_periodic_task(value _unit) {
+value sim_periodic_task(value _unit __attribute__ ((unused))) {
   periodic_task();
   return Val_unit;
 }
@@ -55,7 +57,7 @@ value set_really_lost(value on) {
   return Val_unit;
 }
 
-value sim_rc_task(value _unit) {
+value sim_rc_task(value _unit __attribute__ ((unused))) {
   NormalizePpm(); /** -> rc_values */
   /***  printf("sim_rc_task ppm=%d rc_val=%d\n", ppm_pulses[RADIO_MODE], rc_values[RADIO_MODE]); ***/
   int i;
@@ -160,9 +162,9 @@ value send_event(value event_id) {
   return Val_unit;
 }
 
-value dl_setting(value index, value val) {
-#if defined DlSetting
+value dl_setting(value index __attribute__ ((unused)), 
+		 value val __attribute__ ((unused))) {
+  /** DlSetting macro may be empty: unused attr to get rif of the warning */
   DlSetting(Int_val(index), Double_val(val));
-#endif
   return Val_unit;
 }
diff --git a/sw/simulator/sim_ir.c b/sw/simulator/sim_ir.c
index 6b93a9d87e..2087c0c9f5 100644
--- a/sw/simulator/sim_ir.c
+++ b/sw/simulator/sim_ir.c
@@ -21,5 +21,7 @@ value set_ir(value roll, value top) {
 }
 
 /** Required by infrared.c:ir_init() */
-void adc_buf_channel(void* _1, void* _2, void* _3) {
+void adc_buf_channel(void* a __attribute__ ((unused)),
+		     void* b __attribute__ ((unused)),
+		     void* c __attribute__ ((unused))) {
 }