Ide shows errors on vulkan.hpp bitflag operations. Code still compiles.

the code:
vk::ImageUsageFlags usage = vk::ImageUsageFlagBits::eColorAttachment | vk::ImageUsageFlagBits::eStorage;
gets red underline and whines 'bout binary operator '|' can't be applied to this type.
visual studio doesn't show any problem.

So is it an ide problem or something i just don't understand yet?

library used is vulkan.hpp.