Why is VK_BUFFER_USAGE_STORAGE_BUFFER_BIT required in the buffer_device_address example?

[mahkoh]

The VK_KHR_buffer_device_address example says that VK_BUFFER_USAGE_STORAGE_BUFFER_BIT is required:

Vulkan-Samples/samples/extensions/buffer_device_address/buffer_device_address.cpp

Lines 239 to 242 in 43c23e5

	// To be able to query the buffer device address, we must use the SHADER_DEVICE_ADDRESS_BIT usage flag.
	// STORAGE_BUFFER is also required.
	VkBufferCreateInfo create_info = vkb::initializers::buffer_create_info(
	VK_BUFFER_USAGE_STORAGE_BUFFER_BIT | VK_BUFFER_USAGE_SHADER_DEVICE_ADDRESS_BIT_KHR, mesh_size);

But as far as I can tell, the vulkan specification only requires this bit for descriptors and ray tracing. I don't believe that either of those apply to the example.