diff --git a/include/quaternion.h b/include/quaternion.h
index 9fb5c5a8..5fdff798 100644
--- a/include/quaternion.h
+++ b/include/quaternion.h
@@ -140,7 +140,7 @@ class quaternion
 		quaternion& makeInverse();
 
 		//! Set this quaternion to the linear interpolation between two quaternions
-		/** NOTE: lerp result is *not* a normalized quaternion. In most cases 
+		/** NOTE: lerp result is *not* a normalized quaternion. In most cases
 		you will want to use lerpN instead as most other quaternion functions expect
 		to work with a normalized quaternion.
 		\param q1 First quaternion to be interpolated.
@@ -152,7 +152,7 @@ class quaternion
 		quaternion& lerp(quaternion q1, quaternion q2, f32 time);
 
 		//! Set this quaternion to the linear interpolation between two quaternions and normalize the result
-		/** 
+		/**
 		\param q1 First quaternion to be interpolated.
 		\param q2 Second quaternion to be interpolated.
 		\param time Progress of interpolation. For time=0 the result is
@@ -585,7 +585,7 @@ inline quaternion& quaternion::normalize()
 {
 	// removed conditional branch since it may slow down and anyway the condition was
 	// false even after normalization in some cases.
-	return (*this *= reciprocal_squareroot ( X*X + Y*Y + Z*Z + W*W ));
+	return (*this *= (f32)reciprocal_squareroot ( (f64)(X*X + Y*Y + Z*Z + W*W) ));
 }
 
 // Set this quaternion to the result of the linear interpolation between two quaternions
diff --git a/tests/testQuaternion.cpp b/tests/testQuaternion.cpp
index e8f9189c..b54f0c88 100644
--- a/tests/testQuaternion.cpp
+++ b/tests/testQuaternion.cpp
@@ -18,7 +18,7 @@ inline bool compareQ(const core::vector3df& v, const core::vector3df& turn=core:
 		logTestString("Inequality before quat.toEuler(): %f,%f,%f\n", v.X,v.Y,v.Z);
 		return false;
 	}
-	
+
 	q.toEuler(v2);
 	v2*=core::RADTODEG;
 	v2=v2.rotationToDirection(turn);
@@ -110,7 +110,7 @@ bool testQuatEulerMatrix()
 	core::vector3df v6 = mat.getRotationDegrees()*core::DEGTORAD;
 	// make sure comparison matrix is correct
 	result &= v4.equals(v6);
- 
+
 	core::matrix4 mat2 = q1.getMatrix();
 	result &= mat.equals(mat2, 0.0005f);
 
diff --git a/tests/tests-last-passed-at.txt b/tests/tests-last-passed-at.txt
index 5016da9e..1034815d 100644
--- a/tests/tests-last-passed-at.txt
+++ b/tests/tests-last-passed-at.txt
@@ -1,4 +1,4 @@
-Tests finished. 72 tests of 72 passed.
-Compiled as DEBUG
-Test suite pass at GMT Fri Jan 03 14:40:24 2020
-
+Tests finished. 72 tests of 72 passed.
+Compiled as DEBUG
+Test suite pass at GMT Fri Jan  3 17:05:41 2020
+