diff --git a/pyopencl/array.py b/pyopencl/array.py
index f3dd5e74d467ac175f2c8fcbfa448057ddd19807..16e249456b4a34fc1aef147968bec2cc310d9515 100644
--- a/pyopencl/array.py
+++ b/pyopencl/array.py
@@ -75,6 +75,9 @@ def _get_common_dtype(obj1, obj2, queue):
         raise ValueError("PyOpenCL array has no queue; call .with_queue() to "
                 "add one in order to be able to perform operations")
 
+    # Note: We are calling np.result_type with pyopencl arrays here.
+    # Luckily, np.result_type only looks at the dtype of input arrays as of
+    # numpy v2.1.
     result = np.result_type(obj1, obj2)
 
     if not has_double_support(queue.device):
diff --git a/test/test_array.py b/test/test_array.py
index 4b6488781998af60b7fb8397040c61f47fd804b2..f9ec27a837666269fcbf7e9a9807d73142cdcf77 100644
--- a/test/test_array.py
+++ b/test/test_array.py
@@ -2393,6 +2393,24 @@ def test_xdg_cache_home(ctx_factory):
 # }}}
 
 
+def test_numpy_type_promotion_with_cl_arrays(ctx_factory):
+    ctx = ctx_factory()
+    queue = cl.CommandQueue(ctx)
+
+    class NotReallyAnArray:
+        @property
+        def dtype(self):
+            return np.dtype("float64")
+
+    # Make sure that np.result_type accesses only the dtype attribute of the
+    # class, not (e.g.) its data.
+    assert np.result_type(42, NotReallyAnArray()) == np.float64
+
+    from pyopencl.array import _get_common_dtype
+    assert _get_common_dtype(42, NotReallyAnArray(), queue) == np.float64
+    assert _get_common_dtype(42.0, NotReallyAnArray(), queue) == np.float64
+
+
 if __name__ == "__main__":
     if len(sys.argv) > 1:
         exec(sys.argv[1])