title: How to check enabled features for Qt build?
body: <p>I want to use <code>Qt 5.10.1</code> with <code>Vulkan</code>. I downloaded prebuilt <code>gcc_64</code> version, opened <code>hellowulkanwindow</code> application, set <code>VULKAN_SDK</code> in build environment. But the compilation gives me a lot of errors, for example <code>'QVulkanWindow' does not name a type</code>. It looks like the macro <code>QT_CONFIG(vulkan)</code> return false, but I'm pretty sure that prebuilt version should come with <code>Vulkan</code> enabled.</p>
  
  <p><code>VulkanSDK</code> installed on my system, I can run demos. Also I can run non-qt code which uses <code>Vulkan</code>.</p>
  
  <p>So how to check that feature <code>QT_FEATURE_vulkan</code> is enabled?</p>
  
  <p>Upd: I ran <code>configure -list-features</code> in 5.10.1 sources and it didn't showed me anything related to <code>Vulkan</code>.</p>