diff --git a/sw/airborne/math/pprz_algebra_float.h b/sw/airborne/math/pprz_algebra_float.h
index ca38bec2cb9..53f17178aa1 100644
--- a/sw/airborne/math/pprz_algebra_float.h
+++ b/sw/airborne/math/pprz_algebra_float.h
@@ -313,29 +313,29 @@ struct FloatRates {
 
 /* _m_a2c = _m_a2b comp _m_b2c , aka  _m_a2c = _m_b2c * _m_a2b */
 #define FLOAT_RMAT_COMP(_m_a2c, _m_a2b, _m_b2c) {           \
-    _m_a2c.m[0] = (_m_b2c.m[0]*_m_a2b.m[0] + _m_b2c.m[1]*_m_a2b.m[3] + _m_b2c.m[2]*_m_a2b.m[6]); \
-    _m_a2c.m[1] = (_m_b2c.m[0]*_m_a2b.m[1] + _m_b2c.m[1]*_m_a2b.m[4] + _m_b2c.m[2]*_m_a2b.m[7]); \
-    _m_a2c.m[2] = (_m_b2c.m[0]*_m_a2b.m[2] + _m_b2c.m[1]*_m_a2b.m[5] + _m_b2c.m[2]*_m_a2b.m[8]); \
-    _m_a2c.m[3] = (_m_b2c.m[3]*_m_a2b.m[0] + _m_b2c.m[4]*_m_a2b.m[3] + _m_b2c.m[5]*_m_a2b.m[6]); \
-    _m_a2c.m[4] = (_m_b2c.m[3]*_m_a2b.m[1] + _m_b2c.m[4]*_m_a2b.m[4] + _m_b2c.m[5]*_m_a2b.m[7]); \
-    _m_a2c.m[5] = (_m_b2c.m[3]*_m_a2b.m[2] + _m_b2c.m[4]*_m_a2b.m[5] + _m_b2c.m[5]*_m_a2b.m[8]); \
-    _m_a2c.m[6] = (_m_b2c.m[6]*_m_a2b.m[0] + _m_b2c.m[7]*_m_a2b.m[3] + _m_b2c.m[8]*_m_a2b.m[6]); \
-    _m_a2c.m[7] = (_m_b2c.m[6]*_m_a2b.m[1] + _m_b2c.m[7]*_m_a2b.m[4] + _m_b2c.m[8]*_m_a2b.m[7]); \
-    _m_a2c.m[8] = (_m_b2c.m[6]*_m_a2b.m[2] + _m_b2c.m[7]*_m_a2b.m[5] + _m_b2c.m[8]*_m_a2b.m[8]); \
+    _m_a2c.m[0] = ((_m_b2c).m[0]*(_m_a2b).m[0] + (_m_b2c).m[1]*(_m_a2b).m[3] + (_m_b2c).m[2]*(_m_a2b).m[6]); \
+    _m_a2c.m[1] = ((_m_b2c).m[0]*(_m_a2b).m[1] + (_m_b2c).m[1]*(_m_a2b).m[4] + (_m_b2c).m[2]*(_m_a2b).m[7]); \
+    _m_a2c.m[2] = ((_m_b2c).m[0]*(_m_a2b).m[2] + (_m_b2c).m[1]*(_m_a2b).m[5] + (_m_b2c).m[2]*(_m_a2b).m[8]); \
+    _m_a2c.m[3] = ((_m_b2c).m[3]*(_m_a2b).m[0] + (_m_b2c).m[4]*(_m_a2b).m[3] + (_m_b2c).m[5]*(_m_a2b).m[6]); \
+    _m_a2c.m[4] = ((_m_b2c).m[3]*(_m_a2b).m[1] + (_m_b2c).m[4]*(_m_a2b).m[4] + (_m_b2c).m[5]*(_m_a2b).m[7]); \
+    _m_a2c.m[5] = ((_m_b2c).m[3]*(_m_a2b).m[2] + (_m_b2c).m[4]*(_m_a2b).m[5] + (_m_b2c).m[5]*(_m_a2b).m[8]); \
+    _m_a2c.m[6] = ((_m_b2c).m[6]*(_m_a2b).m[0] + (_m_b2c).m[7]*(_m_a2b).m[3] + (_m_b2c).m[8]*(_m_a2b).m[6]); \
+    _m_a2c.m[7] = ((_m_b2c).m[6]*(_m_a2b).m[1] + (_m_b2c).m[7]*(_m_a2b).m[4] + (_m_b2c).m[8]*(_m_a2b).m[7]); \
+    _m_a2c.m[8] = ((_m_b2c).m[6]*(_m_a2b).m[2] + (_m_b2c).m[7]*(_m_a2b).m[5] + (_m_b2c).m[8]*(_m_a2b).m[8]); \
   }
 
 
 /* _m_a2b = _m_a2c comp_inv _m_b2c , aka  _m_a2b = inv(_m_b2c) * _m_a2c */
 #define FLOAT_RMAT_COMP_INV(_m_a2b, _m_a2c, _m_b2c) {           \
-    _m_a2b.m[0] = (_m_b2c.m[0]*_m_a2c.m[0] + _m_b2c.m[3]*_m_a2c.m[3] + _m_b2c.m[6]*_m_a2c.m[6]); \
-    _m_a2b.m[1] = (_m_b2c.m[0]*_m_a2c.m[1] + _m_b2c.m[3]*_m_a2c.m[4] + _m_b2c.m[6]*_m_a2c.m[7]); \
-    _m_a2b.m[2] = (_m_b2c.m[0]*_m_a2c.m[2] + _m_b2c.m[3]*_m_a2c.m[5] + _m_b2c.m[6]*_m_a2c.m[8]); \
-    _m_a2b.m[3] = (_m_b2c.m[1]*_m_a2c.m[0] + _m_b2c.m[4]*_m_a2c.m[3] + _m_b2c.m[7]*_m_a2c.m[6]); \
-    _m_a2b.m[4] = (_m_b2c.m[1]*_m_a2c.m[1] + _m_b2c.m[4]*_m_a2c.m[4] + _m_b2c.m[7]*_m_a2c.m[7]); \
-    _m_a2b.m[5] = (_m_b2c.m[1]*_m_a2c.m[2] + _m_b2c.m[4]*_m_a2c.m[5] + _m_b2c.m[7]*_m_a2c.m[8]); \
-    _m_a2b.m[6] = (_m_b2c.m[2]*_m_a2c.m[0] + _m_b2c.m[5]*_m_a2c.m[3] + _m_b2c.m[8]*_m_a2c.m[6]); \
-    _m_a2b.m[7] = (_m_b2c.m[2]*_m_a2c.m[1] + _m_b2c.m[5]*_m_a2c.m[4] + _m_b2c.m[8]*_m_a2c.m[7]); \
-    _m_a2b.m[8] = (_m_b2c.m[2]*_m_a2c.m[2] + _m_b2c.m[5]*_m_a2c.m[5] + _m_b2c.m[8]*_m_a2c.m[8]); \
+    _m_a2b.m[0] = ((_m_b2c).m[0]*(_m_a2c).m[0] + (_m_b2c).m[3]*(_m_a2c).m[3] + (_m_b2c).m[6]*(_m_a2c).m[6]); \
+    _m_a2b.m[1] = ((_m_b2c).m[0]*(_m_a2c).m[1] + (_m_b2c).m[3]*(_m_a2c).m[4] + (_m_b2c).m[6]*(_m_a2c).m[7]); \
+    _m_a2b.m[2] = ((_m_b2c).m[0]*(_m_a2c).m[2] + (_m_b2c).m[3]*(_m_a2c).m[5] + (_m_b2c).m[6]*(_m_a2c).m[8]); \
+    _m_a2b.m[3] = ((_m_b2c).m[1]*(_m_a2c).m[0] + (_m_b2c).m[4]*(_m_a2c).m[3] + (_m_b2c).m[7]*(_m_a2c).m[6]); \
+    _m_a2b.m[4] = ((_m_b2c).m[1]*(_m_a2c).m[1] + (_m_b2c).m[4]*(_m_a2c).m[4] + (_m_b2c).m[7]*(_m_a2c).m[7]); \
+    _m_a2b.m[5] = ((_m_b2c).m[1]*(_m_a2c).m[2] + (_m_b2c).m[4]*(_m_a2c).m[5] + (_m_b2c).m[7]*(_m_a2c).m[8]); \
+    _m_a2b.m[6] = ((_m_b2c).m[2]*(_m_a2c).m[0] + (_m_b2c).m[5]*(_m_a2c).m[3] + (_m_b2c).m[8]*(_m_a2c).m[6]); \
+    _m_a2b.m[7] = ((_m_b2c).m[2]*(_m_a2c).m[1] + (_m_b2c).m[5]*(_m_a2c).m[4] + (_m_b2c).m[8]*(_m_a2c).m[7]); \
+    _m_a2b.m[8] = ((_m_b2c).m[2]*(_m_a2c).m[2] + (_m_b2c).m[5]*(_m_a2c).m[5] + (_m_b2c).m[8]*(_m_a2c).m[8]); \
   }