diff --git a/src/svgren/renderer.cpp b/src/svgren/renderer.cpp
index e2c17df..93cbab1 100644
--- a/src/svgren/renderer.cpp
+++ b/src/svgren/renderer.cpp
@@ -126,7 +126,7 @@ void renderer::apply_transformation(const svgdom::transformable::transformation&
 	}
 }
 
-void renderer::apply_transformations(const decltype(svgdom::transformable::transformations) & transformations)
+void renderer::apply_transformations(const decltype(svgdom::transformable::transformations)& transformations)
 {
 	for (auto& t : transformations) {
 		this->apply_transformation(t);
@@ -1340,7 +1340,7 @@ void renderer::visit(const svgdom::rect_element& e)
 	this->render_shape(group_push.is_group_pushed());
 }
 
-const decltype(svgdom::transformable::transformations) & //
+const decltype(svgdom::transformable::transformations)& //
 renderer::gradient_get_transformations(const svgdom::gradient& g)
 {
 	if (g.transformations.size() != 0) {
@@ -1572,7 +1572,7 @@ svgdom::length renderer::gradient_get_fy(const svgdom::radial_gradient_element&
 	return {0, svgdom::length_unit::unknown};
 }
 
-const decltype(svgdom::container::children) & renderer::gradient_get_stops(const svgdom::gradient& g)
+const decltype(svgdom::container::children)& renderer::gradient_get_stops(const svgdom::gradient& g)
 {
 	if (g.children.size() != 0) {
 		return g.children;
@@ -1594,7 +1594,7 @@ const decltype(svgdom::container::children) & renderer::gradient_get_stops(const
 	return g.children;
 }
 
-const decltype(svgdom::styleable::styles) & renderer::gradient_get_styles(const svgdom::gradient& g)
+const decltype(svgdom::styleable::styles)& renderer::gradient_get_styles(const svgdom::gradient& g)
 {
 	if (g.styles.size() != 0) {
 		return g.styles;
@@ -1616,7 +1616,7 @@ const decltype(svgdom::styleable::styles) & renderer::gradient_get_styles(const
 	return g.styles;
 }
 
-const decltype(svgdom::styleable::classes) & renderer::gradient_get_classes(const svgdom::gradient& g)
+const decltype(svgdom::styleable::classes)& renderer::gradient_get_classes(const svgdom::gradient& g)
 {
 	if (!g.classes.empty()) {
 		return g.classes;
diff --git a/src/svgren/renderer.hxx b/src/svgren/renderer.hxx
index 6a2a83e..614e90d 100644
--- a/src/svgren/renderer.hxx
+++ b/src/svgren/renderer.hxx
@@ -74,7 +74,7 @@ public:
 
 	void apply_transformation(const svgdom::transformable::transformation& t);
 
-	void apply_transformations(const decltype(svgdom::transformable::transformations) & transformations);
+	void apply_transformations(const decltype(svgdom::transformable::transformations)& transformations);
 
 	void set_gradient_properties(
 		veg::gradient& gradient, //
@@ -104,7 +104,7 @@ public:
 		const svgdom::length& height
 	);
 
-	const decltype(svgdom::transformable::transformations) & gradient_get_transformations(const svgdom::gradient& g);
+	const decltype(svgdom::transformable::transformations)& gradient_get_transformations(const svgdom::gradient& g);
 	svgdom::coordinate_units gradient_get_units(const svgdom::gradient& g);
 
 	svgdom::length gradient_get_x1(const svgdom::linear_gradient_element& g);
@@ -118,9 +118,9 @@ public:
 	svgdom::length gradient_get_fx(const svgdom::radial_gradient_element& g);
 	svgdom::length gradient_get_fy(const svgdom::radial_gradient_element& g);
 
-	const decltype(svgdom::container::children) & gradient_get_stops(const svgdom::gradient& g);
-	const decltype(svgdom::styleable::styles) & gradient_get_styles(const svgdom::gradient& g);
-	const decltype(svgdom::styleable::classes) & gradient_get_classes(const svgdom::gradient& g);
+	const decltype(svgdom::container::children)& gradient_get_stops(const svgdom::gradient& g);
+	const decltype(svgdom::styleable::styles)& gradient_get_styles(const svgdom::gradient& g);
+	const decltype(svgdom::styleable::classes)& gradient_get_classes(const svgdom::gradient& g);
 	svgdom::gradient::spread_method gradient_get_spread_method(const svgdom::gradient& g);
 
 	decltype(svgdom::styleable::presentation_attributes) //
diff --git a/src/svgren/util.cpp b/src/svgren/util.cpp
index c094774..c58dd72 100644
--- a/src/svgren/util.cpp
+++ b/src/svgren/util.cpp
@@ -51,7 +51,7 @@ real svgren::percent_to_fraction(const svgdom::length& l)
 	return 0;
 }
 
-renderer_viewport_push::renderer_viewport_push(renderer& r, const decltype(old_viewport) & viewport) :
+renderer_viewport_push::renderer_viewport_push(renderer& r, const decltype(old_viewport)& viewport) :
 	r(r),
 	old_viewport(r.viewport)
 {
diff --git a/src/svgren/util.hxx b/src/svgren/util.hxx
index efa36a8..deb6530 100644
--- a/src/svgren/util.hxx
+++ b/src/svgren/util.hxx
@@ -52,7 +52,7 @@ class renderer_viewport_push
 	r4::vector2<real> old_viewport;
 
 public:
-	renderer_viewport_push(renderer& r, const decltype(old_viewport) & viewport);
+	renderer_viewport_push(renderer& r, const decltype(old_viewport)& viewport);
 
 	renderer_viewport_push(const renderer_viewport_push&) = delete;
 	renderer_viewport_push& operator=(const renderer_viewport_push&) = delete;
diff --git a/tests/unit/samples.cpp b/tests/unit/samples.cpp
index ace4f86..5a3fa12 100644
--- a/tests/unit/samples.cpp
+++ b/tests/unit/samples.cpp
@@ -60,6 +60,7 @@ const tst::set set("samples", [](tst::suite& suite){
 #if CFG_COMPILER == CFG_COMPILER_MSVC
 #	pragma warning(disable : 4996)
 #endif
+            // NOLINTNEXTLINE(clang-diagnostic-deprecated-declarations, "false positive")
             auto res = svgren::render(*dom);
 #if CFG_COMPILER == CFG_COMPILER_MSVC
 #	pragma warning(enable: 4996)