python
diff --git a/‎Misc/NEWS.d/next/Library/2026-06-18-12-48-03.gh-issue-151640.R4c3Fx.rst‎
Lines changed: 3 additions & 0 deletions b/‎Misc/NEWS.d/next/Library/2026-06-18-12-48-03.gh-issue-151640.R4c3Fx.rst‎
Lines changed: 3 additions & 0 deletions
diff --git a/‎Misc/NEWS.d/next/Library/2026-06-18-12-48-03.gh-issue-151640.rst‎
Lines changed: 0 additions & 3 deletions b/‎Misc/NEWS.d/next/Library/2026-06-18-12-48-03.gh-issue-151640.rst‎
Lines changed: 0 additions & 3 deletions
@@ -0,0 +1,3 @@
+Fix a data race in :class:`io.BytesIO` in free-threaded builds when
+whole-buffer reads or peeks, or :meth:`~io.BytesIO.getvalue`, share the
+internal buffer with concurrent writes.
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	+Fix a data race in :class:`io.BytesIO` in free-threaded builds when
	`2`	+whole-buffer reads or peeks, or :meth:`~io.BytesIO.getvalue`, share the
	`3`	`+internal buffer with concurrent writes.`