I'm creating descriptor pool with poolSizeCount == 0 and pPoolSizes == nullptr and i still can allocate various number of descriptors of any type. There are no validation errors on Linux, only on Windows (but code works).
Another case: i'm providing VkDescriptorPoolSize with only 1 VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, but can allocate more VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER or even descriptors of other types (in this case errors don't occur on both Linux and Windows).
Why is this happening?
It is not technically invalid usage to exceed the pool limits in general:
If a call to
vkAllocateDescriptorSetswould cause the total number of descriptor sets allocated from the pool to exceed the value ofvkDescriptorPoolCreateInfo::maxSetsused to createpAllocateInfo->descriptorPool, then the allocation may fail due to lack of space in the descriptor pool. Similarly, the allocation may fail due to lack of space if the call tovkAllocateDescriptorSetswould cause the number of any given descriptor type to exceed the sum of all thedescriptorCountmembers of each element ofVkDescriptorPoolCreateInfo::pPoolSizeswith a member equal to that type.
Note the use of the word "may", which allows implementations to fail but doesn't require them to do so. This means that you're supposed to stay within those limits, but nobody's going to stop you if you exceed them and get away with it.
Now, it is a violation of valid usage to pass no sizes at all:
poolSizeCountmust be greater than 0
And the appropriate layer should catch that. But outside of layers, you just achieve undefined behavior. Which can be "appears to work".
