This infinite loop:

def f():
  a=b=0
  while 1:
    if a<b: pass

f()

doesn't respond to a Ctrl-C interrupt. If you modify the loop in various ways, like removing the function wrapper, then Ctrl-C works fine. It can be interrupted with Ctrl-\. This occurs if the program is run from a file or in the interactive interpreter.

Tested on Python 2.7.3 / Linux 3.2.0-64 x86_64, and Python 2.7.6 / Linux 3.13.0-27.

Reproducible: always
Expected behaviour: Ctrl-C interrupts program
Actual beviour: Ctrl-C prints ^C