Minimal Vulkan example of VkDebugUtilsMessengerEXT usage doesn't output anything? - vulkan

Question

The following Vulkan program attempts to create an instance and setup a VkDebugUtilsMessengerEXT - but when run it doesn't output anything:
#include <stdlib.h>
#include <stdio.h>
#include <vulkan/vulkan.h>
VkBool32 VKAPI_PTR debug_utils_messenger_callback(
VkDebugUtilsMessageSeverityFlagBitsEXT messageSeverity,
VkDebugUtilsMessageTypeFlagsEXT messageType,
const VkDebugUtilsMessengerCallbackDataEXT* pCallbackData,
void* pUserData) {
printf("%s", pCallbackData->pMessage);
return VK_FALSE;
}
int main() {
// create instance
VkInstanceCreateInfo instance_create_info = {};
instance_create_info.sType = VK_STRUCTURE_TYPE_INSTANCE_CREATE_INFO;
const char* layers[] = {"VK_LAYER_LUNARG_standard_validation"};
instance_create_info.ppEnabledLayerNames = layers;
instance_create_info.enabledLayerCount = 1;
const char* extensions[] = {VK_EXT_DEBUG_UTILS_EXTENSION_NAME};
instance_create_info.enabledExtensionCount = 1;
instance_create_info.ppEnabledExtensionNames = extensions;
VkInstance instance;
if (VK_SUCCESS != vkCreateInstance(&instance_create_info, NULL, &instance))
exit(EXIT_FAILURE);
// load kCreateDebugUtilsMessengerEXT
PFN_vkCreateDebugUtilsMessengerEXT pvkCreateDebugUtilsMessengerEXT =
(PFN_vkCreateDebugUtilsMessengerEXT)
vkGetInstanceProcAddr(instance, "vkCreateDebugUtilsMessengerEXT");
if (pvkCreateDebugUtilsMessengerEXT == NULL)
exit(EXIT_FAILURE);
// create debug utils messenger
VkDebugUtilsMessengerCreateInfoEXT debug_utils_messenger_create_info = {};
debug_utils_messenger_create_info.sType = VK_STRUCTURE_TYPE_DEBUG_UTILS_MESSENGER_CREATE_INFO_EXT;
debug_utils_messenger_create_info.messageSeverity =
VK_DEBUG_UTILS_MESSAGE_SEVERITY_ERROR_BIT_EXT |
VK_DEBUG_UTILS_MESSAGE_SEVERITY_WARNING_BIT_EXT |
VK_DEBUG_UTILS_MESSAGE_SEVERITY_INFO_BIT_EXT |
VK_DEBUG_UTILS_MESSAGE_SEVERITY_VERBOSE_BIT_EXT;
debug_utils_messenger_create_info.messageType =
VK_DEBUG_UTILS_MESSAGE_TYPE_GENERAL_BIT_EXT |
VK_DEBUG_UTILS_MESSAGE_TYPE_PERFORMANCE_BIT_EXT |
VK_DEBUG_UTILS_MESSAGE_TYPE_VALIDATION_BIT_EXT;
debug_utils_messenger_create_info.pfnUserCallback = debug_utils_messenger_callback;
VkDebugUtilsMessengerEXT debug_utils_messenger;
if (VK_SUCCESS != pvkCreateDebugUtilsMessengerEXT(instance, &debug_utils_messenger_create_info, NULL, &debug_utils_messenger))
exit(EXIT_FAILURE);
// destroy instance
vkDestroyInstance(instance, NULL);
}
Why not? I would expect that it outputs some debug messages from the debug_utils_messenger_callback?

Answer 1

Object Tracker does track debug utils objects, but it looks like the layer is only reporting objects belonging to undestroyed device objects at DestroyInstance-time, and debugutils shows up in that list. It should go in a separate Instance object list and get spit out at DestroyInstance time.
A github issue has been submitted: https://github.com/KhronosGroup/Vulkan-ValidationLayers/issues/658