fix(numba): Add warnings for objectmode

Author: aseyboldt

pytensor/link/numba/dispatch/basic.py

@@ -560,11 +560,18 @@ def {fn_name}({", ".join(input_names)}):
 @numba_funcify.register(Subtensor)
 @numba_funcify.register(AdvancedSubtensor1)
 def numba_funcify_Subtensor(op, node, **kwargs):
-    subtensor_def_src = create_index_func(
-        node, objmode=isinstance(op, AdvancedSubtensor)
-    )
+    objmode = isinstance(op, AdvancedSubtensor)
+    if objmode:
+        warnings.warn(
+            ("Numba will use object mode to allow run " "AdvancedSubtensor."),
+            UserWarning,
+        )
+
+    subtensor_def_src = create_index_func(node, objmode=objmode)
 
-    global_env = {"np": np, "objmode": numba.objmode}
+    global_env = {"np": np}
+    if objmode:
+        global_env["objmode"] = numba.objmode
 
     subtensor_fn = compile_function_src(
         subtensor_def_src, "subtensor", {**globals(), **global_env}
@@ -575,11 +582,18 @@ def numba_funcify_Subtensor(op, node, **kwargs):
 
 @numba_funcify.register(IncSubtensor)
 def numba_funcify_IncSubtensor(op, node, **kwargs):
-    incsubtensor_def_src = create_index_func(
-        node, objmode=isinstance(op, AdvancedIncSubtensor)
-    )
+    objmode = isinstance(op, AdvancedIncSubtensor)
+    if objmode:
+        warnings.warn(
+            ("Numba will use object mode to allow run " "AdvancedIncSubtensor."),
+            UserWarning,
+        )
+
+    incsubtensor_def_src = create_index_func(node, objmode=objmode)
 
-    global_env = {"np": np, "objmode": numba.objmode}
+    global_env = {"np": np}
+    if objmode:
+        global_env["objmode"] = numba.objmode
 
     incsubtensor_fn = compile_function_src(
         incsubtensor_def_src, "incsubtensor", {**globals(), **global_env}