diff --git a/test/gtc/gtc_quaternion.cpp b/test/gtc/gtc_quaternion.cpp
index 49ac157b..db410fc4 100644
--- a/test/gtc/gtc_quaternion.cpp
+++ b/test/gtc/gtc_quaternion.cpp
@@ -291,9 +291,23 @@ int test_quat_ctr()
 	return Error;
 }
 
+int test_size()
+{
+	int Error = 0;
+
+	Error += 16 == sizeof(glm::quat) ? 0 : 1;
+	Error += 32 == sizeof(glm::dquat) ? 0 : 1;
+	Error += glm::quat().length() == 4 ? 0 : 1;
+	Error += glm::dquat().length() == 4 ? 0 : 1;
+	Error += glm::quat::length() == 4 ? 0 : 1;
+	Error += glm::dquat::length() == 4 ? 0 : 1;
+
+	return Error;
+}
+
 int main()
 {
-	int Error(0);
+	int Error = 0;
 
 	Error += test_quat_ctr();
 	Error += test_quat_mul_vec();
@@ -307,6 +321,7 @@ int main()
 	Error += test_quat_normalize();
 	Error += test_quat_euler();
 	Error += test_quat_slerp();
+	Error += test_size();
 
 	return Error;
 }
diff --git a/test/gtx/gtx_dual_quaternion.cpp b/test/gtx/gtx_dual_quaternion.cpp
index b06bba35..73d400f0 100644
--- a/test/gtx/gtx_dual_quaternion.cpp
+++ b/test/gtx/gtx_dual_quaternion.cpp
@@ -174,15 +174,30 @@ int test_dual_quat_ctr()
 	return Error;
 }
 
+int test_size()
+{
+	int Error = 0;
+
+	Error += 32 == sizeof(glm::dualquat) ? 0 : 1;
+	Error += 64 == sizeof(glm::ddualquat) ? 0 : 1;
+	Error += glm::dualquat().length() == 2 ? 0 : 1;
+	Error += glm::ddualquat().length() == 2 ? 0 : 1;
+	Error += glm::dualquat::length() == 2 ? 0 : 1;
+	Error += glm::ddualquat::length() == 2 ? 0 : 1;
+
+	return Error;
+}
+
 int main()
 {
-	int Error(0);
+	int Error = 0;
 
 	Error += test_dual_quat_ctr();
 	Error += test_dquat_type();
 	Error += test_scalars();
 	Error += test_inverse();
 	Error += test_mul();
+	Error += test_size();
 
 	return Error;
 }
diff --git a/test/gtx/gtx_quaternion.cpp b/test/gtx/gtx_quaternion.cpp
index d3938fb1..12e12b2a 100644
--- a/test/gtx/gtx_quaternion.cpp
+++ b/test/gtx/gtx_quaternion.cpp
@@ -91,7 +91,7 @@ int test_log()
 
 int main()
 {
-	int Error(0);
+	int Error = 0;
 
 	Error += test_log();
 	Error += test_rotation();