Author Name: Al Grant
Original Redmine Issue: 1381 from https://www.veripool.org

Original Assignee: Wilson Snyder (@wsnyder)

Compiling a source file with declarations but no top module:

logic a;

results in an error with no location:

%Error: Duplicate declaration of cell: $unit
%Error: ... Location of original declaration
%Error: Exiting due to 1 error(s)

A diagnostic about no module definition might be reasonable, but this looks like Verilator has internally tried to do something twice that it should only do once and failed a self-check. A duplicate declaration diagnostic without locations for the declarations seems like a misdiagnosis.