diff --git a/sw/airborne/arch/lpc21/i2c_hw.c b/sw/airborne/arch/lpc21/i2c_hw.c
index b3e0c54281..d91352db4b 100644
--- a/sw/airborne/arch/lpc21/i2c_hw.c
+++ b/sw/airborne/arch/lpc21/i2c_hw.c
@@ -33,16 +33,16 @@
 // I2C Automaton //
 ///////////////////
 
-static inline void I2cSendStart(struct i2c_periph* p) {
+__attribute__ ((always_inline)) static inline void I2cSendStart(struct i2c_periph* p) {
   p->status = I2CStartRequested;
   ((i2cRegs_t *)(p->reg_addr))->conset = _BV(STA);
 }
 
-static inline void I2cSendAck(void* reg) {
+__attribute__ ((always_inline)) static inline void I2cSendAck(void* reg) {
   ((i2cRegs_t *)reg)->conset = _BV(AA);
 }
 
-static inline void I2cEndOfTransaction(struct i2c_periph* p) {
+__attribute__ ((always_inline)) static inline void I2cEndOfTransaction(struct i2c_periph* p) {
   // handle fifo here
   p->trans_extract_idx++;
   if (p->trans_extract_idx >= I2C_TRANSACTION_QUEUE_LEN)
@@ -56,18 +56,18 @@ static inline void I2cEndOfTransaction(struct i2c_periph* p) {
   }
 }
 
-static inline void I2cFinished(struct i2c_periph* p, struct i2c_transaction* t) {
+__attribute__ ((always_inline)) static inline void I2cFinished(struct i2c_periph* p, struct i2c_transaction* t) {
   // transaction finished with success
   t->status = I2CTransSuccess;
   I2cEndOfTransaction(p);
 }
 
-static inline void I2cSendStop(struct i2c_periph* p, struct i2c_transaction* t) {
+__attribute__ ((always_inline)) static inline void I2cSendStop(struct i2c_periph* p, struct i2c_transaction* t) {
   ((i2cRegs_t *)(p->reg_addr))->conset = _BV(STO);
   I2cFinished(p,t);
 }
 
-static inline void I2cFail(struct i2c_periph* p, struct i2c_transaction* t) {
+__attribute__ ((always_inline)) static inline void I2cFail(struct i2c_periph* p, struct i2c_transaction* t) {
   ((i2cRegs_t *)(p->reg_addr))->conset = _BV(STO);
   t->status = I2CTransFailed;
   p->status = I2CFailed;
@@ -75,24 +75,24 @@ static inline void I2cFail(struct i2c_periph* p, struct i2c_transaction* t) {
   I2cEndOfTransaction(p);
 }
 
-static inline void I2cSendByte(void* reg, uint8_t b) {
+__attribute__ ((always_inline)) static inline void I2cSendByte(void* reg, uint8_t b) {
   ((i2cRegs_t *)reg)->dat = b;
 }
 
-static inline void I2cReceive(void* reg, bool_t ack) {
+__attribute__ ((always_inline)) static inline void I2cReceive(void* reg, bool_t ack) {
   if (ack) ((i2cRegs_t *)reg)->conset = _BV(AA);
   else ((i2cRegs_t *)reg)->conclr = _BV(AAC);
 }
 
-static inline void I2cClearStart(void* reg) {
+__attribute__ ((always_inline)) static inline void I2cClearStart(void* reg) {
   ((i2cRegs_t *)reg)->conclr = _BV(STAC);
 }
 
-static inline void I2cClearIT(void* reg) {
+__attribute__ ((always_inline)) static inline void I2cClearIT(void* reg) {
   ((i2cRegs_t *)reg)->conclr = _BV(SIC);
 }
 
-static inline void I2cAutomaton(int32_t state, struct i2c_periph* p) {
+__attribute__ ((always_inline)) static inline void I2cAutomaton(int32_t state, struct i2c_periph* p) {
   struct i2c_transaction* trans = p->trans[p->trans_extract_idx];
   switch (state) {
     case I2C_START:
diff --git a/sw/airborne/firmwares/rotorcraft/actuators/supervision.c b/sw/airborne/firmwares/rotorcraft/actuators/supervision.c
index 9a114641ee..012b2402a0 100644
--- a/sw/airborne/firmwares/rotorcraft/actuators/supervision.c
+++ b/sw/airborne/firmwares/rotorcraft/actuators/supervision.c
@@ -59,13 +59,13 @@ void supervision_init(void) {
   supervision.nb_failure = 0;
 }
 
-static inline void offset_commands(int32_t offset) {
+__attribute__ ((always_inline)) static inline void offset_commands(int32_t offset) {
   uint8_t j;
   for (j=0; j<SUPERVISION_NB_MOTOR; j++)
     supervision.commands[j] += (offset);
 }
 
-static inline void bound_commands(void) {
+__attribute__ ((always_inline)) static inline void bound_commands(void) {
   uint8_t j;
   for (j=0; j<SUPERVISION_NB_MOTOR; j++)
     Bound(supervision.commands[j],
diff --git a/sw/airborne/firmwares/rotorcraft/guidance/guidance_h.c b/sw/airborne/firmwares/rotorcraft/guidance/guidance_h.c
index 6bc46336c2..d2ff49ef0b 100644
--- a/sw/airborne/firmwares/rotorcraft/guidance/guidance_h.c
+++ b/sw/airborne/firmwares/rotorcraft/guidance/guidance_h.c
@@ -221,7 +221,7 @@ void guidance_h_run(bool_t  in_flight) {
 //#define MAX_BANK (65536)
 #define MAX_BANK (98000)
 
-static inline void  guidance_h_hover_run(void) {
+__attribute__ ((always_inline)) static inline void  guidance_h_hover_run(void) {
 
   /* compute position error    */
   VECT2_DIFF(guidance_h_pos_err, ins_ltp_pos, guidance_h_pos_sp);
@@ -279,7 +279,7 @@ static inline void  guidance_h_hover_run(void) {
 #define NAV_MAX_BANK BFP_OF_REAL(0.35,REF_ANGLE_FRAC)
 #define HOLD_DISTANCE POS_BFP_OF_REAL(10.)
 
-static inline void  guidance_h_nav_run(bool_t in_flight) {
+__attribute__ ((always_inline)) static inline void  guidance_h_nav_run(bool_t in_flight) {
 
   /* convert our reference to generic representation */
 #ifdef GUIDANCE_H_USE_REF
@@ -368,7 +368,7 @@ static inline void  guidance_h_nav_run(bool_t in_flight) {
 
 }
 
-static inline void guidance_h_hover_enter(void) {
+__attribute__ ((always_inline)) static inline void guidance_h_hover_enter(void) {
 
   VECT2_COPY(guidance_h_pos_sp, ins_ltp_pos);
 
@@ -378,7 +378,7 @@ static inline void guidance_h_hover_enter(void) {
 
 }
 
-static inline void guidance_h_nav_enter(void) {
+__attribute__ ((always_inline)) static inline void guidance_h_nav_enter(void) {
 
   INT32_VECT2_NED_OF_ENU(guidance_h_pos_sp, navigation_carrot);
   struct Int32Vect2 pos,speed,zero;
diff --git a/sw/airborne/firmwares/rotorcraft/guidance/guidance_v.c b/sw/airborne/firmwares/rotorcraft/guidance/guidance_v.c
index 075314c2b8..dc4a659cf5 100644
--- a/sw/airborne/firmwares/rotorcraft/guidance/guidance_v.c
+++ b/sw/airborne/firmwares/rotorcraft/guidance/guidance_v.c
@@ -82,7 +82,7 @@ int32_t guidance_v_z_sum_err;
   }
 
 
-static inline void run_hover_loop(bool_t in_flight);
+__attribute__ ((always_inline)) static inline void run_hover_loop(bool_t in_flight);
 
 
 void guidance_v_init(void) {
@@ -232,7 +232,7 @@ void guidance_v_run(bool_t in_flight) {
 
 #define MAX_BANK_COEF (BFP_OF_REAL(RadOfDeg(30.),INT32_TRIG_FRAC))
 
-static inline void run_hover_loop(bool_t in_flight) {
+__attribute__ ((always_inline)) static inline void run_hover_loop(bool_t in_flight) {
 
   /* convert our reference to generic representation */
   int64_t tmp  = gv_z_ref>>(GV_Z_REF_FRAC - INT32_POS_FRAC);
diff --git a/sw/airborne/firmwares/rotorcraft/guidance/guidance_v_ref.h b/sw/airborne/firmwares/rotorcraft/guidance/guidance_v_ref.h
index dba603bddb..bcdd473413 100644
--- a/sw/airborne/firmwares/rotorcraft/guidance/guidance_v_ref.h
+++ b/sw/airborne/firmwares/rotorcraft/guidance/guidance_v_ref.h
@@ -96,14 +96,14 @@ int64_t gv_z_ref;
 int32_t gv_zd_ref;
 int32_t gv_zdd_ref;
 
-static inline void gv_set_ref(int32_t alt, int32_t speed, int32_t accel) {
+__attribute__ ((always_inline)) static inline void gv_set_ref(int32_t alt, int32_t speed, int32_t accel) {
   int64_t new_z = ((int64_t)alt)<<(GV_Z_REF_FRAC - INT32_POS_FRAC);
   gv_z_ref   = new_z;
   gv_zd_ref  = speed>>(INT32_SPEED_FRAC - GV_ZD_REF_FRAC);
   gv_zdd_ref = accel>>(INT32_ACCEL_FRAC - GV_ZDD_REF_FRAC);
 }
 
-static inline void gv_update_ref_from_z_sp(int32_t z_sp) {
+__attribute__ ((always_inline)) static inline void gv_update_ref_from_z_sp(int32_t z_sp) {
 
   gv_z_ref  += gv_zd_ref;
   gv_zd_ref += gv_zdd_ref;
@@ -135,7 +135,7 @@ static inline void gv_update_ref_from_z_sp(int32_t z_sp) {
 }
 
 
-static inline void gv_update_ref_from_zd_sp(int32_t zd_sp) {
+__attribute__ ((always_inline)) static inline void gv_update_ref_from_zd_sp(int32_t zd_sp) {
 
   gv_z_ref  += gv_zd_ref;
   gv_zd_ref += gv_zdd_ref;
diff --git a/sw/airborne/subsystems/ahrs/ahrs_int_cmpl_euler.c b/sw/airborne/subsystems/ahrs/ahrs_int_cmpl_euler.c
index 80bdfaa72d..546159d568 100644
--- a/sw/airborne/subsystems/ahrs/ahrs_int_cmpl_euler.c
+++ b/sw/airborne/subsystems/ahrs/ahrs_int_cmpl_euler.c
@@ -154,7 +154,7 @@ void ahrs_update_mag(void) {
 }
 
 /* measures phi and theta assuming no dynamic acceleration ?!! */
-static inline void get_phi_theta_measurement_fom_accel(int32_t* phi_meas, int32_t* theta_meas, struct Int32Vect3 accel) {
+__attribute__ ((always_inline)) static inline void get_phi_theta_measurement_fom_accel(int32_t* phi_meas, int32_t* theta_meas, struct Int32Vect3 accel) {
 
   INT32_ATAN2(*phi_meas, -accel.y, -accel.z);
   int32_t cphi;
@@ -167,7 +167,7 @@ static inline void get_phi_theta_measurement_fom_accel(int32_t* phi_meas, int32_
 }
 
 /* measure psi by projecting magnetic vector in local tangeant plan */
-static inline void get_psi_measurement_from_mag(int32_t* psi_meas, int32_t phi_est, int32_t theta_est, struct Int32Vect3 mag) {
+__attribute__ ((always_inline)) static inline void get_psi_measurement_from_mag(int32_t* psi_meas, int32_t phi_est, int32_t theta_est, struct Int32Vect3 mag) {
 
   int32_t sphi;
   PPRZ_ITRIG_SIN(sphi, phi_est);
@@ -196,7 +196,7 @@ static inline void get_psi_measurement_from_mag(int32_t* psi_meas, int32_t phi_e
 
 /* Compute ltp to imu rotation in quaternion and rotation matrice representation
    from the euler angle representation */
-static inline void compute_imu_quat_and_rmat_from_euler(void) {
+__attribute__ ((always_inline)) static inline void compute_imu_quat_and_rmat_from_euler(void) {
 
   /* Compute LTP to IMU quaternion */
   INT32_QUAT_OF_EULERS(ahrs.ltp_to_imu_quat, ahrs.ltp_to_imu_euler);
@@ -205,7 +205,7 @@ static inline void compute_imu_quat_and_rmat_from_euler(void) {
 
 }
 
-static inline void compute_body_orientation(void) {
+__attribute__ ((always_inline)) static inline void compute_body_orientation(void) {
 
   /* Compute LTP to BODY quaternion */
   INT32_QUAT_COMP_INV(ahrs.ltp_to_body_quat, ahrs.ltp_to_imu_quat, imu.body_to_imu_quat);
diff --git a/sw/airborne/subsystems/ins/vf_float.c b/sw/airborne/subsystems/ins/vf_float.c
index bc33bb0fcf..8638b93035 100644
--- a/sw/airborne/subsystems/ins/vf_float.c
+++ b/sw/airborne/subsystems/ins/vf_float.c
@@ -122,7 +122,7 @@ void vff_propagate(float accel) {
   // update covariance
   Pp = Pm - K*H*Pm;
 */
-static inline void update_z_conf(float z_meas, float conf) {
+__attribute__ ((always_inline)) static inline void update_z_conf(float z_meas, float conf) {
   vff_z_meas = z_meas;
 
   const float y = z_meas - vff_z;
@@ -179,7 +179,7 @@ void vff_update_z_conf(float z_meas, float conf) {
   // update covariance
   Pp = Pm - K*H*Pm;
 */
-static inline void update_vz_conf(float vz, float conf) {
+__attribute__ ((always_inline)) static inline void update_vz_conf(float vz, float conf) {
   const float yd = vz - vff_zdot;
   const float S = vff_P[1][1] + conf;
   const float K1 = vff_P[0][1] * 1/S;