BUG:saving a modified .py file after loading a module kills the kernel

[ghost]

Edit:
I'm still not sure on the exact conditions required to reproduce, but
this seems to happen when I spawn some threads in an imported module,
followed by, I kid not, editing and saving one of the source files of the
module, or even some files of the ipython package itself.
Very strange, and the only error message is what appears below
in the original post. ideas?

I'm working on some of my own multithreaded code in qtconsole and
getting frequent "restart kernel" prompts, probably due to kernel crashes.

All I'm seeing in the shell is:

λ ipython qtconsole
[IPKernelApp] To connect another client to this kernel, use:
[IPKernelApp] --existing kernel-2995.json
Traceback (most recent call last):
  File "<string>", line 1, in <module>
NameError: name 'f' is not defined

Can I get the ipython kernel to break into pdb when it crashes?
Are there other forms of built-in tooling for debugging this?

[ghost]

Resolved and not a problem in IPython.