Fix broken check in save_mem_new_scan

Without extracting the underlying numeric value of a constant TensorVariable `length`, `stop == length` would always fail.

Fix broken check in save_mem_new_scan
bdface7e · Ricardo Vieira · Ricardo Vieira · 0b632bdb · bdface7e
--- a/pytensor/scan/rewriting.py
+++ b/pytensor/scan/rewriting.py
@@ -1339,7 +1339,7 @@ def save_mem_new_scan(fgraph, node):
                    stop = at.extract_constant(cf_slice[0].stop)
                else:
                    stop = at.extract_constant(cf_slice[0]) + 1
-                if stop == maxsize or stop == length:
+                if stop == maxsize or stop == at.extract_constant(length):
                    stop = None
                else:
                    # there is a **gotcha** here ! Namely, scan returns an