Synthesis tool optimizing out block?

You could also use the report_clocks command.....but I haven't tried this yet, so I'm not sure what data TimeQuest will give you. Currently, I am using TimeQuest to read in the netlist and SDC file, and then looking at the initial report to see what clocks have not been constrained. This is a good starting point for me since I am not intimately familar with the design.

I've used the Fitter report in the past, but didn't think about using it for the clock resources. But I'd rather use TimeQuest to give me the info, since I'm using information supplied by that tool to properly constrain the clocks. But you do bring up a good point, something that I need to think about after I finish editing the SDC file. The Fitter as well as TimeQuest reads in the SDC file, so it's important that the contrainst will apply to both tools.