Merge branch '3.14' into feat/gc-gen-3.14

Author: sergey-miryanov

.gitattributes

@@ -34,6 +34,9 @@ Lib/test/xmltestdata/*                     noeol
 Lib/venv/scripts/common/activate text eol=lf
 Lib/venv/scripts/posix/* text eol=lf
 
+# Prevent GitHub's web conflict editor from converting LF to CRLF
+*.rst text eol=lf
+
 # CRLF files
 [attr]dos text eol=crlf
 

.github/workflows/mypy.yml

@@ -18,6 +18,7 @@ on:
       - "Tools/build/compute-changes.py"
       - "Tools/build/deepfreeze.py"
       - "Tools/build/generate-build-details.py"
+      - "Tools/build/generate_levenshtein_examples.py"
       - "Tools/build/generate_sbom.py"
       - "Tools/build/generate_stdlib_module_names.py"
       - "Tools/build/mypy.ini"

.github/workflows/reusable-san.yml

@@ -40,17 +40,15 @@ jobs:
         # Install clang
         wget https://apt.llvm.org/llvm.sh
         chmod +x llvm.sh
+        sudo ./llvm.sh 20
+        sudo update-alternatives --install /usr/bin/clang clang /usr/bin/clang-20 100
+        sudo update-alternatives --set clang /usr/bin/clang-20
+        sudo update-alternatives --install /usr/bin/clang++ clang++ /usr/bin/clang++-20 100
+        sudo update-alternatives --set clang++ /usr/bin/clang++-20
 
         if [ "${SANITIZER}" = "TSan" ]; then
-          sudo ./llvm.sh 17  # gh-121946: llvm-18 package is temporarily broken
-          sudo update-alternatives --install /usr/bin/clang clang /usr/bin/clang-17 100
-          sudo update-alternatives --set clang /usr/bin/clang-17
-          sudo update-alternatives --install /usr/bin/clang++ clang++ /usr/bin/clang++-17 100
-          sudo update-alternatives --set clang++ /usr/bin/clang++-17
           # Reduce ASLR to avoid TSan crashing
           sudo sysctl -w vm.mmap_rnd_bits=28
-        else
-          sudo ./llvm.sh 20
         fi
 
     - name: Sanitizer option setup

Lib/test/test_marshal.py

@@ -357,6 +357,9 @@ def f():
         code = f.__code__
         a = []
         code = code.replace(co_consts=code.co_consts + (a,))
+        # This test creates a reference loop which leads to reference leaks,
+        # so we need to break the loop manually. See gh-148722.
+        self.addCleanup(a.clear)
         a.append(code)
         for v in range(marshal.version + 1):
             self.assertRaises(ValueError, marshal.dumps, code, v)
@@ -404,10 +407,12 @@ def test_loads_abnormal_reference_loops(self):
         self.assertIs(a[0][None], a)
 
         # Direct self-reference which cannot be created in Python.
-        data = b'\xa8\x01\x00\x00\x00r\x00\x00\x00\x00' # (<R>,)
-        a = marshal.loads(data)
-        self.assertIsInstance(a, tuple)
-        self.assertIs(a[0], a)
+        # This creates a reference loop which cannot be collected.
+        if False:
+            data = b'\xa8\x01\x00\x00\x00r\x00\x00\x00\x00' # (<R>,)
+            a = marshal.loads(data)
+            self.assertIsInstance(a, tuple)
+            self.assertIs(a[0], a)
 
         # Direct self-references which cannot be created in Python
         # because of unhashability.

Misc/NEWS.d/next/Library/2026-02-22-00-00-00.gh-issue-145105.csv-reader-reentrant.rst

@@ -1,2 +1,2 @@
-Fix crash in :mod:`csv` reader when iterating with a re-entrant iterator
-that calls :func:`next` on the same reader from within ``__next__``.
+Fix crash in :mod:`csv` reader when iterating with a re-entrant iterator
+that calls :func:`next` on the same reader from within ``__next__``.

Tools/build/generate_levenshtein_examples.py

@@ -13,7 +13,7 @@
 _CASE_COST = 1
 
 
-def _substitution_cost(ch_a, ch_b):
+def _substitution_cost(ch_a: str, ch_b: str) -> int:
     if ch_a == ch_b:
         return 0
     if ch_a.lower() == ch_b.lower():
@@ -22,7 +22,7 @@ def _substitution_cost(ch_a, ch_b):
 
 
 @lru_cache(None)
-def levenshtein(a, b):
+def levenshtein(a: str, b: str) -> int:
     if not a or not b:
         return (len(a) + len(b)) * _MOVE_COST
     option1 = levenshtein(a[:-1], b[:-1]) + _substitution_cost(a[-1], b[-1])
@@ -31,7 +31,7 @@ def levenshtein(a, b):
     return min(option1, option2, option3)
 
 
-def main():
+def main() -> None:
     parser = argparse.ArgumentParser(description=__doc__)
     parser.add_argument('output_path', metavar='FILE', type=str)
     parser.add_argument('--overwrite', dest='overwrite', action='store_const',
@@ -48,7 +48,7 @@ def main():
         )
         return
 
-    examples = set()
+    examples: set[tuple[str, str, int]] = set()
     # Create a lot of non-empty examples, which should end up with a Gauss-like
     # distribution for even costs (moves) and odd costs (case substitutions).
     while len(examples) < 9990:

Tools/build/mypy.ini

@@ -8,6 +8,7 @@ files =
     Tools/build/compute-changes.py,
     Tools/build/deepfreeze.py,
     Tools/build/generate-build-details.py,
+    Tools/build/generate_levenshtein_examples.py,
     Tools/build/generate_sbom.py,
     Tools/build/generate_stdlib_module_names.py,
     Tools/build/verify_ensurepip_wheels.py,