Update what's new with the latest GC improvements (GH-17708)

diff --git a/Doc/whatsnew/3.9.rst b/Doc/whatsnew/3.9.rst
index 64361bb17f8a47d2aa1e42451502ecf7d5fbf3c3..b315604af5110c1f8e6a1a177bc61b7a8de0eac3 100644 (file)
--- a/Doc/whatsnew/3.9.rst
+++ b/Doc/whatsnew/3.9.rst
@@ -159,6 +159,14 @@ Added constants :data:`~fcntl.F_OFD_GETLK`, :data:`~fcntl.F_OFD_SETLK`
 and :data:`~fcntl.F_OFD_SETLKW`.
 (Contributed by Dong-hee Na in :issue:`38602`.)
 
+gc
+--
+
+When the garbage collector makes a collection in which some objects resurrect
+(they are reachable from outside the isolated cycles after the finalizers have
+been executed), do not block the collection of all objects that are still
+unreachable. (Contributed by Pablo Galindo and Tim Peters in :issue:`38379`.)
+
 os
 --