# Buggy code
def new_error_context(fmt_, *args, **kwargs):
    """
    A contextmanager that prepend contextual information to any exception
    raised within.  If the exception type is not an instance of NumbaError,
    it will be wrapped into a InternalError.   The exception class can be
    changed by providing a "errcls_" keyword argument with the exception
    constructor.

    The first argument is a message that describes the context.  It can be a
    format string.  If there are additional arguments, it will be used as
    ``fmt_.format(*args, **kwargs)`` to produce the final message string.
    """
    errcls = kwargs.pop("errcls_", InternalError)
    try:
        yield
    except NumbaError as e:
        e.add_context(_format_msg(fmt_, args, kwargs))
        raise
    except Exception as e:
        newerr = errcls(e).add_context(_format_msg(fmt_, args, kwargs))
        six.reraise(type(newerr), newerr, sys.exc_info()[2])


# Traceback (TypeError)
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-15-3b23f7331ceb> in <module>()
----> 1 @jit(arg_types=[numba.double], ret_type=numba.double)
2 def is_REALLY_five(some_value):
3     for i in range(5):
4         if some_value == 5.0:
5             return 1.0

/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/numba/decorators.pyc in _jit(func)
77                   "garbage collected!" % (func,))
78         t = Translate(func, *args, **kws)
---> 79         t.translate()
80         __tr_map__[func] = t
81         return t.get_ctypes_func(llvm)

/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/numba/translate.pyc in translate(self)
926                     # Ensure we are playing with locals that might
927                     # actually precede the next block.
--> 928                     self.check_locals(i)
929
930                 self.crnt_block = i

/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/site-packages/numba/translate.pyc in check_locals(self, i)
1135                 else:
1136                     assert next_locals is not None, "Internal compiler error!"
-> 1137             self._locals = next_locals[:]
1138
1139     def get_ctypes_func(self, llvm=True):

TypeError: 'NoneType' object has no attribute '__getitem__'

# Fixed code
def new_error_context(fmt_, *args, **kwargs):
    """
    A contextmanager that prepend contextual information to any exception
    raised within.  If the exception type is not an instance of NumbaError,
    it will be wrapped into a InternalError.   The exception class can be
    changed by providing a "errcls_" keyword argument with the exception
    constructor.

    The first argument is a message that describes the context.  It can be a
    format string.  If there are additional arguments, it will be used as
    ``fmt_.format(*args, **kwargs)`` to produce the final message string.
    """
    errcls = kwargs.pop("errcls_", InternalError)

    loc = kwargs.get("loc", None)
    if loc is not None and not loc.filename.startswith(_numba_path):
        loc_info.update(kwargs)

    try:
        yield
    except NumbaError as e:
        e.add_context(_format_msg(fmt_, args, kwargs))
        raise
    except Exception as e:
        newerr = errcls(e).add_context(_format_msg(fmt_, args, kwargs))
        six.reraise(type(newerr), newerr, sys.exc_info()[2])