No out of bounds check during advanced array indexing

Numba ignores any indices that are out of bounds for a given array shape. This behavior is present in both basic and advanced indexing.

import numpy as np
import numba

@numba.njit
def something():
    arr = np.ones((3,3))
    arr[100] = 0
    arr[:, np.array([2,3,5,100])] = 0
    return arr

print(something()) # Does not raise error, ignores the out of bound indices completely.
print(something.py_func()) # Raises out of bounds error

Not sure if we should be considering this as a bug or a feature 😃

Should be easily fixed by adding a bounds check during indexing during function runtime.

[stuartarchibald]

@kc611 suggest adding:

diff --git a/numba/np/arrayobj.py b/numba/np/arrayobj.py
index 850bd1d..5b1d48e 100644
--- a/numba/np/arrayobj.py
+++ b/numba/np/arrayobj.py
@@ -1617,7 +1617,8 @@ def fancy_setslice(context, builder, sig, args, index_types, indices):
     dest_ptr = cgutils.get_item_pointer2(context, builder, dest_data,
                                          dest_shapes, dest_strides,
                                          aryty.layout, dest_indices,
-                                         wraparound=False)
+                                         wraparound=False,
+                                         boundscheck=context.enable_boundscheck)
     store_item(context, builder, aryty, val, dest_ptr)

see if that helps?

[kc611]

Thank you that was exactly what I was looking for.