address review

Author: picnixz

Lib/test/test_code.py

@@ -1132,13 +1132,13 @@ def foo(a, b):
 
         c = foo.__code__
 
-        co_nlocalsplus = len({*c.co_varnames, *c.co_cellvars, *c.co_freevars})
-        # anything below that limit is a valid co_stacksize
-        evil_stacksize = int(_testcapi.INT_MAX / 16 - co_nlocalsplus)
+        # The exact limit depends on co_nlocalsplus, so we do not hardcode it.
+        too_large_stacksize = _testcapi.INT_MAX // 16
+        ok_stacksize = too_large_stacksize // 2
 
         with self.assertRaisesRegex(OverflowError, "stack size is too large"):
-            c.__replace__(co_stacksize=evil_stacksize)
-        c.__replace__(co_stacksize=evil_stacksize - 1)
+            c.__replace__(co_stacksize=too_large_stacksize)
+        c.__replace__(co_stacksize=ok_stacksize)
 
 
 def isinterned(s):

Misc/NEWS.d/next/Core_and_Builtins/2024-10-29-11-47-19.gh-issue-126119.xbAvxt.rst

@@ -1,4 +1,4 @@
-Fix a crash in DEBUG builds due to an overflow when the :attr:`co_stacksize
-<codeobject.co_stacksize>` field of a :ref:`code object <code-objects>` is
-set to an absurdly large integer.
+Fix a crash in DEBUG builds due to a lack of overflow checks when setting
+the :attr:`co_stacksize <codeobject.co_stacksize>` field of a :ref:`code
+object <code-objects>` via :meth:`~object.__replace__`.
 Reported by Valery Fedorenko. Patch by Bénédikt Tran.