Hello,
1) Hopefully you're working with a SIMH vax from the master branch at https://github.com/simh/simh
It's the latest SIMH from pkgsrc, which is currently simh-4.0.0.20180919.
2) You should be able to pick a simulator from there and configure it effectively the same configuration as your physical machine (there are many vax simulators that are now provided).If you can reproduce the failure, I'll track down what is or isn't working.
Thanks! If you'd like, you can fetch ready-to-use images from the links here: http://mail-index.netbsd.org/port-vax/2020/08/13/msg003608.htmlvax.ini is set to 128 megs, so compiling Perl should work. Changing that to 256 megs should cause Perl to fail at regexec.c.
John Klos