# Buggy code
def copy_propagate_update_analysis(stmt, var_dict, array_analysis):
    """update array analysis data during copy propagation.
    If an array is in defs of a statement, we update its size variables.
    """
    array_shape_classes = array_analysis.array_shape_classes
    class_sizes = array_analysis.class_sizes
    array_size_vars = array_analysis.array_size_vars
    # find defs of stmt
    def_set = set()
    if isinstance(stmt, ir.Assign):
        def_set.add(stmt.target.name)
    for T, def_func in analysis.ir_extension_defs.items():
        if isinstance(stmt, T):
            def_set = def_func(stmt)
    # update analysis for arrays in defs
    for var in def_set:
        if var in array_shape_classes:
            if var in array_size_vars:
                array_size_vars[var] = replace_vars_inner(
                    array_size_vars[var], var_dict
                )
            shape_corrs = array_shape_classes[var]
            for c in shape_corrs:
                if c != -1:
                    class_sizes[c] = replace_vars_inner(class_sizes[c], var_dict)
    return


# 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 copy_propagate_update_analysis(stmt, var_dict, array_analysis):
    """update array analysis data during copy propagation.
    If an array is in defs of a statement, we update its size variables.
    """
    array_shape_classes = array_analysis.array_shape_classes
    class_sizes = array_analysis.class_sizes
    array_size_vars = array_analysis.array_size_vars
    # find defs of stmt
    def_set = set()
    if isinstance(stmt, ir.Assign):
        def_set.add(stmt.target.name)
    for T, def_func in analysis.ir_extension_usedefs.items():
        if isinstance(stmt, T):
            _, def_set = def_func(stmt)
    # update analysis for arrays in defs
    for var in def_set:
        if var in array_shape_classes:
            if var in array_size_vars:
                array_size_vars[var] = replace_vars_inner(
                    array_size_vars[var], var_dict
                )
            shape_corrs = array_shape_classes[var]
            for c in shape_corrs:
                if c != -1:
                    class_sizes[c] = replace_vars_inner(class_sizes[c], var_dict)
    return