Fix find_suitable_device logic to conditionally increment cl_device_c…

…ount

samples/extensions/khr/externalmemory/vulkan_utils.h

@@ -256,6 +256,12 @@ find_suitable_device(VkInstance instance,
  }
  }
 
+ if (!cl_device_count)
+ {
+ printf("No suitable OpenCL Vulkan-compatible devices available\n");
+ goto platforms;
+ }
+
  // For each OpenCL device, query its Vulkan-compatible device UUID and
  // add it to the list of candidates. The device must support the
  // cl_khr_device_uuid extension for us to be able to query the device's
@@ -275,7 +281,7 @@ find_suitable_device(VkInstance instance,
 
  for (cl_uint cl_candidate_id = 0;
  cl_candidate_id < cl_platform_devices_count;
- ++cl_candidate_id, ++cl_device_count)
+ ++cl_candidate_id)
  {
  cl_device_id device = cl_util_get_device(
  platform_id, cl_candidate_id, CL_DEVICE_TYPE_ALL, &error);
@@ -292,6 +298,7 @@ find_suitable_device(VkInstance instance,
  memcpy(candidate.uuid, &vk_candidate_uuid,
  sizeof(cl_uchar) * CL_UUID_SIZE_KHR);
  cl_candidates[cl_device_count] = candidate;
+ cl_device_count++;
  }
  }
  }