When simulating the circuit diagram DiodeTest.cir, an interesting phenomenon occurred. The simulation abnormally terminates when using Ngspice 42, but it completes successfully with Ngspice 43. Does this suggest that there was a bug in version 42, which has been fixed in the new version?
To facilitate the reproduction of the issue, the netlist file and the models used are provided in the attachment.
According to the manual, chapter 2.1.4.5 Ground node: Each circuit has to have a ground node (gnd or 0)!
Your circuits don't have, so you cannot draw any conclusion from the results.
The rshunt option is not guaranteed to help here.
Thank you very much for your response. However, the same netlist can be simulated in the latest version 43.