//module param_list_no_hash #( // Correct syntax
     FOO=1
) (
     output bar
);

assign bar = FOO;

endmodule

         /usr/local/bin/verilator_bin_dbg -cc module.v --debug
Starting Verilator 3.922 2018-03-17 rev UNKNOWN_REV
- V3Os.cpp:57:        export SYSTEMC_ARCH=cygwin # From sysname 'cygwin_nt-10.0'
- V3File.cpp:205:        --check-times failed: no input obj_dir/Vmodule__verFiles.dat
- V3GraphTest.cpp:356:selfTest:
- V3ParseImp.cpp:97:  parseFile: module
  Preprocessing module.v
- V3PreShell.cpp:137:     Reading module.v
- V3ParseImp.cpp:164: Lexing module.v
%Error: export VERILATOR_ROOT=
%Error: /usr/local/bin/verilator_bin_dbg -cc module.v --debug
%Error: Command Failed /usr/local/bin/verilator_bin_dbg -cc module.v --debug

</pre