diff --git a/glm/gtx/int_10_10_10_2.inl b/glm/gtx/int_10_10_10_2.inl
index 8ab6a1d2..446f5354 100644
--- a/glm/gtx/int_10_10_10_2.inl
+++ b/glm/gtx/int_10_10_10_2.inl
@@ -11,7 +11,7 @@ namespace glm{
 namespace gtx{
 namespace int_10_10_10_2
 {
-	dword uint10_10_10_2_cast(glm::vec4 const & v)
+	inline dword uint10_10_10_2_cast(glm::vec4 const & v)
 	{
 		return dword(uint(v.x * 2047.f) << 0 | uint(v.y * 2047.f) << 10 | uint(v.z * 2047.f) << 20 | uint(v.w * 3.f) << 30);
 	}