Output of attached profiler_c_code.py example:
---
haypo@selma$ ./python profiler_c_code.py 
(<frame object at 0xf9d788>, 'call', None)
(<frame object at 0xf9d788>, 'return', 'h')
(<frame object at 0xf9d788>, 'call', None)
(<frame object at 0xf9d788>, 'return', 'e')
(<frame object at 0xf9d788>, 'call', None)
(<frame object at 0xf9d788>, 'return', 'l')
(<frame object at 0xf9d788>, 'call', None)
(<frame object at 0xf9d788>, 'return', 'l')
(<frame object at 0xf9d788>, 'call', None)
(<frame object at 0xf9d788>, 'return', 'o')
(<frame object at 0xf9d498>, 'c_call', <built-in function setprofile>)
---

Except of sys.setprofile(), the profiler doesn't see any C calls! list() and map() are simply "hidden".

So tools like coverage miss a lot of C call? Again, is it a compromise between performance and correctness, or just a regular bug?