I think I have fixed the original problem via Issue 14285 (fully in 3.5+, partly in 2.7). It involved a bit more than checking ImportError.name, because runpy catches other exceptions like AttributeError, which do not identify a module name.

That leaves Laura’s error with the bad *.pyc file. I propose bad-pyc.patch, which adds the sys.modules check to fix the error message, and adds a test case. I think this patch should be applicable to Python 2 as well.