diff --git a/glm/gtx/simd_vec4.inl b/glm/gtx/simd_vec4.inl
index ae5a250f..e8261fcb 100644
--- a/glm/gtx/simd_vec4.inl
+++ b/glm/gtx/simd_vec4.inl
@@ -285,7 +285,7 @@ namespace glm
 		//{
 		//  return max(-a, a);
 		//}
-		detail::fvec4SIMD abs
+		inline detail::fvec4SIMD abs
 		(
 			detail::fvec4SIMD const & x
 		)