These packages are susceptible to bugs when confronted with non-ASCII
characters.
See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94182.
It takes some time to analyze and fix these individually, therefore they
are only marked as "needs work".
VeriWell is a full Verilog simulator. It supports nearly all of the
IEEE1364-1995 standard, as well as PLI 1.0.
Yes, VeriWell *is* the same simulator that was sold by Wellspring Solutions in
the mid-1990 and was included with the Thomas and Moorby book.