Why illegal clocks are reported in Triple Speed Ethernet IP when TimeQuest report unconstranint path is executed?

Description

When you put multiple instances of TSE on your design, you may see some illegal clocks reported in report_ucp command of TimeQuest. This is due to the multi defined derive_pll_clocks command to the same source port as the different clock names.

Resolution

You can avoid this to comment out derive_pll_clocks commands in your multiple reading sdc files except reading last one.