diff --git a/src/VkBootstrap.cpp b/src/VkBootstrap.cpp
index ca72957..929ef96 100644
--- a/src/VkBootstrap.cpp
+++ b/src/VkBootstrap.cpp
@@ -1341,20 +1341,20 @@ PhysicalDeviceSelector& PhysicalDeviceSelector::set_required_features(VkPhysical
 }
 #if defined(VKB_VK_API_VERSION_1_2)
 // Just calls add_required_features
-PhysicalDeviceSelector& PhysicalDeviceSelector::set_required_features_11(VkPhysicalDeviceVulkan11Features features_11) {
-    features_11.sType = VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_VULKAN_1_1_FEATURES;
+PhysicalDeviceSelector& PhysicalDeviceSelector::set_required_features_11(VkPhysicalDeviceVulkan11Features const& features_11) {
+    assert(features_11.sType == VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_VULKAN_1_1_FEATURES);
     add_required_extension_features(features_11);
     return *this;
 }
-PhysicalDeviceSelector& PhysicalDeviceSelector::set_required_features_12(VkPhysicalDeviceVulkan12Features features_12) {
-    features_12.sType = VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_VULKAN_1_2_FEATURES;
+PhysicalDeviceSelector& PhysicalDeviceSelector::set_required_features_12(VkPhysicalDeviceVulkan12Features const& features_12) {
+    assert(features_12.sType == VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_VULKAN_1_2_FEATURES);
     add_required_extension_features(features_12);
     return *this;
 }
 #endif
 #if defined(VKB_VK_API_VERSION_1_3)
-PhysicalDeviceSelector& PhysicalDeviceSelector::set_required_features_13(VkPhysicalDeviceVulkan13Features features_13) {
-    features_13.sType = VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_VULKAN_1_3_FEATURES;
+PhysicalDeviceSelector& PhysicalDeviceSelector::set_required_features_13(VkPhysicalDeviceVulkan13Features const& features_13) {
+    assert(features_13.sType == VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_VULKAN_1_3_FEATURES);
     add_required_extension_features(features_13);
     return *this;
 }
diff --git a/src/VkBootstrap.h b/src/VkBootstrap.h
index 80a07ef..0e53fcc 100644
--- a/src/VkBootstrap.h
+++ b/src/VkBootstrap.h
@@ -629,15 +629,15 @@ class PhysicalDeviceSelector {
 #if defined(VKB_VK_API_VERSION_1_2)
     // Require a physical device which supports the features in VkPhysicalDeviceVulkan11Features.
     // Must have vulkan version 1.2 - This is due to the VkPhysicalDeviceVulkan11Features struct being added in 1.2, not 1.1
-    PhysicalDeviceSelector& set_required_features_11(VkPhysicalDeviceVulkan11Features features_11);
+    PhysicalDeviceSelector& set_required_features_11(VkPhysicalDeviceVulkan11Features const& features_11);
     // Require a physical device which supports the features in VkPhysicalDeviceVulkan12Features.
     // Must have vulkan version 1.2
-    PhysicalDeviceSelector& set_required_features_12(VkPhysicalDeviceVulkan12Features features_12);
+    PhysicalDeviceSelector& set_required_features_12(VkPhysicalDeviceVulkan12Features const& features_12);
 #endif
 #if defined(VKB_VK_API_VERSION_1_3)
     // Require a physical device which supports the features in VkPhysicalDeviceVulkan13Features.
     // Must have vulkan version 1.3
-    PhysicalDeviceSelector& set_required_features_13(VkPhysicalDeviceVulkan13Features features_13);
+    PhysicalDeviceSelector& set_required_features_13(VkPhysicalDeviceVulkan13Features const& features_13);
 #endif
 
     // Used when surface creation happens after physical device selection.