From b54831eb35fa314e41b0c8625a62cc1e3a1f63f8 Mon Sep 17 00:00:00 2001
From: esadomer <54475303+esadomer@users.noreply.github.com>
Date: Tue, 13 Oct 2026 19:50:24 +0300
Subject: [PATCH 1/2] gh-159336: Accept GCC warnings without an option suffix

---
 Lib/test/test_tools/test_check_warnings.py | 29 ++++++++++++++++++++++
 Tools/build/check_warnings.py              |  4 ++-
 2 files changed, 32 insertions(+), 1 deletion(-)
 create mode 100644 Lib/test/test_tools/test_check_warnings.py

diff --git a/Lib/test/test_tools/test_check_warnings.py b/Lib/test/test_tools/test_check_warnings.py
new file mode 100644
index 000000000000000..3dee4c8880d8ea9
--- /dev/null
+++ b/Lib/test/test_tools/test_check_warnings.py
@@ -0,0 +1,29 @@
+import importlib
+import unittest
+
+from test.test_tools import imports_under_tool, skip_if_missing
+
+
+skip_if_missing("build")
+with imports_under_tool("build"):
+    check_warnings = importlib.import_module("check_warnings")
+
+
+class CheckWarningsTests(unittest.TestCase):
+    def test_warning_options(self):
+        for compiler, suffix, option in (
+            ("gcc", "", ""),
+            ("gcc", " [-Wunused-variable]", "-Wunused-variable"),
+            ("clang", " [-Wunused-variable]", "-Wunused-variable"),
+        ):
+            with self.subTest(compiler=compiler, suffix=suffix):
+                warnings = check_warnings.extract_warnings_from_compiler_output(
+                    "source.c:1:2: warning: example" + suffix, compiler)
+                self.assertEqual(warnings, [{
+                    "file": "source.c", "line": "1", "column": "2",
+                    "message": "example", "option": option,
+                }])
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/Tools/build/check_warnings.py b/Tools/build/check_warnings.py
index 44ccf9708ad72f0..5041641ff2a4171 100644
--- a/Tools/build/check_warnings.py
+++ b/Tools/build/check_warnings.py
@@ -100,7 +100,9 @@ def extract_warnings_from_compiler_output(
                     "line": match.group("line"),
                     "column": match.group("column"),
                     "message": match.group("message"),
-                    "option": match.group("option").lstrip("[").rstrip("]"),
+                    "option": (match.group("option") or "")
+                    .lstrip("[")
+                    .rstrip("]"),
                 })
             except AttributeError:
                 print(

From 5d9affd19b6bad5743a0378cb27ea676754c8285 Mon Sep 17 00:00:00 2001
From: esadomer <54475303+esadomer@users.noreply.github.com>
Date: Tue, 13 Oct 2026 20:08:29 +0300
Subject: [PATCH 2/2] gh-159336: Add NEWS entry for
 warnings-optional-gcc-option

---
 .../Tools-Demos/2026-10-13-20-08-28.gh-issue-159336.wGccOp.rst  | 2 ++
 1 file changed, 2 insertions(+)
 create mode 100644 Misc/NEWS.d/next/Tools-Demos/2026-10-13-20-08-28.gh-issue-159336.wGccOp.rst

diff --git a/Misc/NEWS.d/next/Tools-Demos/2026-10-13-20-08-28.gh-issue-159336.wGccOp.rst b/Misc/NEWS.d/next/Tools-Demos/2026-10-13-20-08-28.gh-issue-159336.wGccOp.rst
new file mode 100644
index 000000000000000..072bd6eb0f75c6f
--- /dev/null
+++ b/Misc/NEWS.d/next/Tools-Demos/2026-10-13-20-08-28.gh-issue-159336.wGccOp.rst
@@ -0,0 +1,2 @@
+Fix ``Tools/build/check_warnings.py`` to accept GCC diagnostics that
+omit the warning-option suffix.