You can clone with
Simpler implementation of multiplication.
Remove excess variable.
Handle scope of complex guards when writing case in functions.
Fix warning and typo.
I no longer need to declare string and number tables early.
change not to v_not.
Some compilers do not accept the not symbol.
Add Kato to the list.
Macintosh compilers do not support ident.
Catch module instantiation arrays.
Fix overlap of identifiers when multiple modules used.
Fix up width matching in structural bitwise operators.
Unary reduction operators do not set their operand width
Support case in functions.
support if-else in function definitions.
Mark the line numbers of NetCondit nodes.
Handle selecting memory words at run time.
Accept memory words as parameter to $display.
Include some block matching from Larry.
Update xilinx-hints.txt from Larry.
Include the scope in named gates.
Fix up compiling with configured -ldl switch.
Handle systems that need underscores in symbols.
Compile time problems with vpi_user.h
add the -m flag.
$dumpall checkpointing in VCD dump.
missing break is switch.
Support structural XNOR.
Add the XNOR operator.
Support for multiple VPI modules.
Catch some parameter problems.
Multiplication all the way to simulation.
Elaborate net widths of constants to as small
as is possible, obeying context constraints.
Comparison operators can handle operands with
minor type syntax fix for stubborn C++ compilers.