From f5e0986230f0cefc76208b0c2eea1bace5e6c37c Mon Sep 17 00:00:00 2001
From: Alexander Larsson <alexl@redhat.com>
Date: Thu, 30 Nov 2017 14:48:15 +0100
Subject: [PATCH] vulkan: Don't crash if vkEnumeratePhysicalDevices fails

---
 gdk/gdkvulkancontext.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/gdk/gdkvulkancontext.c b/gdk/gdkvulkancontext.c
index f44253479e..3fd697a8af 100644
--- a/gdk/gdkvulkancontext.c
+++ b/gdk/gdkvulkancontext.c
@@ -599,10 +599,9 @@ gdk_display_create_vulkan_device (GdkDisplay  *display,
 {
   uint32_t i, j;
 
-  uint32_t n_devices;
+  uint32_t n_devices = 0;
   GDK_VK_CHECK(vkEnumeratePhysicalDevices, display->vk_instance, &n_devices, NULL);
-  VkPhysicalDevice *devices = g_newa (VkPhysicalDevice, n_devices);
-  GDK_VK_CHECK(vkEnumeratePhysicalDevices, display->vk_instance, &n_devices, devices);
+  VkPhysicalDevice *devices;
 
   if (n_devices == 0)
     {
@@ -612,6 +611,9 @@ gdk_display_create_vulkan_device (GdkDisplay  *display,
       return FALSE;
     }
 
+  devices = g_newa (VkPhysicalDevice, n_devices);
+  GDK_VK_CHECK(vkEnumeratePhysicalDevices, display->vk_instance, &n_devices, devices);
+
   for (i = 0; i < n_devices; i++)
     {
       VkPhysicalDeviceProperties props;