diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 63f746b2c2543e46054704b775cfc3591074409b..c55e0f46c17fc7c84b568dad5e4ce0f698866cf5 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2023-12-31  Uros Bizjak  <ubizjak@gmail.com>
+	    Roger Sayle  <roger@nextmovesoftware.com>
+
+	PR target/43644
+	* config/i386/i386.md (*add<dwi>3_doubleword_concat_zext): Tweak
+	order of instructions after split, to minimize number of moves.
+
 2023-12-29  Jan Hubicka  <jh@suse.cz>
 
 	* config/i386/x86-tune.def (X86_TUNE_AVOID_128FMA_CHAINS,
diff --git a/gcc/DATESTAMP b/gcc/DATESTAMP
index d3a1eb5640c8cb130d927395d639e0e0d5d127d6..72e8e2938b8112e943b84b7c205cd2c8f59799b2 100644
--- a/gcc/DATESTAMP
+++ b/gcc/DATESTAMP
@@ -1 +1 @@
-20231231
+20240101
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 6b2f90853af4e98bd3b40044c857bb122c2579f3..7e37126ebee6714f98ef6ce96cf08e6de83915de 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2023-12-31  Uros Bizjak  <ubizjak@gmail.com>
+	    Roger Sayle  <roger@nextmovesoftware.com>
+
+	PR target/43644
+	* gcc.target/i386/pr43644-2.c: Expect 2 movq instructions.
+
 2023-12-30  Martin Uecker  <uecker@tugraz.at>
 
 	* gcc.dg/c23-tag-9.c: New test.
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 2e0407adfc6ca2a109969e3f2c160a9d61be40d0..f97165b4992cc0e1d672b3632e4a4be2bbc1c938 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,28 @@
+2023-12-31  Hans-Peter Nilsson  <hp@axis.com>
+
+	* testsuite/20_util/hash/quality.cc: Increase timeout by a factor 3.
+
+2023-12-31  François Dumont  <fdumont@gcc.gnu.org>
+
+	* include/bits/hashtable.h: Move comment about all equivalent values
+	being next to each other in the class documentation header.
+	(_M_reinsert_node, _M_merge_unique): Implement small size optimization.
+	(_M_find_tr, _M_count_tr, _M_equal_range_tr): Likewise.
+
+2023-12-31  François Dumont  <fdumont@gcc.gnu.org>
+
+	* testsuite/performance/23_containers/insert/54075.cc: Add lookup on unknown entries
+	w/o copy to see potential impact of memory fragmentation enhancements.
+	* testsuite/performance/23_containers/insert/unordered_multiset_hint.cc: Enhance hash
+	functor to make it perfect, exactly 1 entry per bucket. Also use hash functor tagged as
+	slow or not to bench w/o hash code cache.
+	* testsuite/performance/23_containers/insert/unordered_set_hint.cc: New test case. Like
+	previous one but using std::unordered_set.
+	* testsuite/performance/23_containers/insert/unordered_set_range_insert.cc: New test case.
+	Check performance of range-insertion compared to individual insertions.
+	* testsuite/performance/23_containers/insert_erase/unordered_small_size.cc: Add same bench
+	but after a copy to demonstrate impact of enhancements regarding memory fragmentation.
+
 2023-12-22  Christophe Lyon  <christophe.lyon@linaro.org>
 
 	* Makefile.am: Allow overriding EXEPCT.