You may observe Quartus® II software report unconstrained paths while running quartus_sta with the
--sdc option to perform timing analysis. This behavior may occur even though there are no unconstrained paths when running a full compilation.If youuse the
--sdc optionfor the
quartus_sta command, the software uses only the constraints in the specified Synopsys Design Constraints (.sdc) file for timing analysis, but not the embedded timing constraints in your design files.
Workaround / Fix
To avoid this behavior, do one of the following actions:
Include the command
read_sdc -hdlwithin your specified .sdc file to have the software use the embedded constraints.
--sdcoption. Without the
--sdcoption, the software performs timing analysis using the embeddedconstraints in design files and the .sdc files in your project.