Internal Error: Sub-system: QSYM, File: /quartus/ccl/qsym/qsym_namespace.cpp, Line: 176

Description

Due to a problem in the Intel® Quartus® Prime Pro Edition software version 20.2 and earlier, you may see the internal error mentioned above when you fully compile your design. This happens for the Windows* 10 only but not in Linux.

Additionally, you will also see a fitter error as shown below

The fitter cannot place 1 periphery component(s) due to conflicts with existing constraints ( 1 clock core fanout(s)).

Resolution

This problem is fixed beginning with the Intel® Quartus® Prime Pro Edition software version 20.3 .