New detail: sending these values further to fragment shader AND writing them to an attachment (did it to verify deugger is sane first) leads to correctly working render pass as if those values were extracted correctly. But debugger still shows them like on the screenshot - mostly zeroes.

Basic repro case based on CPU-GPU-Synchronization sample does not have this problem "unfortanutely". This is probably a combination of multiple factors that cannot be that easily recreated in a sample project because, well, our code base is big and lots of Metal features are used for every frame it renders. I'm afraid I can't even share binary right now :(

Hi. Thank you for the response. Fast math is disabled already :( I'll try to create a sample project and post feedback.