gh-155823: Fix stale stack on _SEND_VIRTUAL_TIER_TWO exhausted exit (GH-155844)

Author: aisk

Lib/test/test_capi/test_opt.py

@@ -5821,6 +5821,20 @@ def testfunc(n):
         self.assertIn("_FOR_ITER_GEN_FRAME", uops)
         self.assertIn("_SEND_VIRTUAL_TIER_TWO", uops)
 
+    def test_send_virtual_exhausted(self):
+        # gh-155823: warm up on a non-empty list, then take the exhausted exit.
+        def gen(x):
+            yield from x
+        def testfunc(n, x):
+            total = 0
+            for _ in range(n):
+                for v in gen(x):
+                    total += v
+            return total
+
+        testfunc(TIER2_THRESHOLD * 10, [1])
+        self.assertEqual(testfunc(1000, []), 0)
+
     def test_binary_op_subscr_init_frame(self):
         class B:
             def __getitem__(self, other):

Misc/NEWS.d/next/Core_and_Builtins/2026-08-15-20-31-20.gh-issue-155823.OhNmzi.rst

@@ -0,0 +1,4 @@
+Fix a JIT bug where the side exit taken when a virtual iterator is exhausted
+left a stale value on the stack, so the tier one interpreter resumed with
+corrupted state and ``yield from`` raised :exc:`AttributeError` instead of
+finishing normally.

Python/bytecodes.c

@@ -1786,8 +1786,6 @@ dummy_func(
                 if (index < 0) {
                     ERROR_NO_POP();
                 }
-                next = none;
-                DEAD(none);
                 EXIT_IF(true);
             }
             DEAD(none);