Clean up warnings from release build
diff --git a/tests/vkrenderframework.cpp b/tests/vkrenderframework.cpp
index b5e528c..9d6d991 100644
--- a/tests/vkrenderframework.cpp
+++ b/tests/vkrenderframework.cpp
@@ -1041,7 +1041,7 @@
 
 VkShaderObj::VkShaderObj(VkDeviceObj *device, const char * shader_code, VkShaderStage stage, VkRenderFramework *framework)
 {
-    VkResult err = VK_SUCCESS;
+    VkResult U_ASSERT_ONLY err = VK_SUCCESS;
     std::vector<unsigned int> spv;
     VkShaderCreateInfo createInfo;
     VkShaderModuleCreateInfo moduleCreateInfo;