+2023-11-08 Jonathan Wakely <jwakely@redhat.com>
+
+ Backported from master:
+ 2023-11-06 Jonathan Wakely <jwakely@redhat.com>
+
+ * include/std/expected (expected::and_then, expected::or_else):
+ Add string literals to static assertions.
+ * include/std/optional (optional::and_then, optional::or_else):
+ Likewise.
+
+2023-11-08 Feng Jisen <J1senn@outlook.com>
+
+ Backported from master:
+ 2023-11-04 Feng Jisen <J1senn@outlook.com>
+
+ * include/bits/utility.h (_Nth_type): Remove redundant partial
+ specialization.
+
+2023-11-08 Jonathan Wakely <jwakely@redhat.com>
+
+ Backported from master:
+ 2023-11-02 Jonathan Wakely <jwakely@redhat.com>
+
+ PR libstdc++/112314
+ * include/std/string_view (string_view::remove_suffix): Add
+ debug assertion.
+ * testsuite/21_strings/basic_string_view/modifiers/remove_prefix/debug.cc:
+ New test.
+ * testsuite/21_strings/basic_string_view/modifiers/remove_suffix/debug.cc:
+ New test.
+
+2023-11-08 Jonathan Wakely <jwakely@redhat.com>
+
+ Backported from master:
+ 2023-11-02 Jonathan Wakely <jwakely@redhat.com>
+
+ * acinclude.m4 (GLIBCXX_ENABLE_C99): Fix snprintf checks.
+ * configure: Regenerate.
+
+2023-11-08 Jonathan Wakely <jwakely@redhat.com>
+
+ Backported from master:
+ 2023-10-26 Jonathan Wakely <jwakely@redhat.com>
+
+ PR libstdc++/112089
+ * include/std/shared_mutex (shared_lock::unlock): Change errc
+ constant to operation_not_permitted.
+ * testsuite/30_threads/shared_lock/locking/112089.cc: New test.
+
+2023-11-08 Jonathan Wakely <jwakely@redhat.com>
+
+ Backported from master:
+ 2023-10-26 Jonathan Wakely <jwakely@redhat.com>
+
+ * testsuite/20_util/duration/io.cc: Double timeout using
+ dg-timeout-factor.
+ * testsuite/std/time/day/io.cc: Likewise.
+ * testsuite/std/time/format.cc: Likewise.
+ * testsuite/std/time/hh_mm_ss/io.cc: Likewise.
+ * testsuite/std/time/month/io.cc: Likewise.
+ * testsuite/std/time/month_day/io.cc: Likewise.
+ * testsuite/std/time/month_day_last/io.cc: Likewise.
+ * testsuite/std/time/month_weekday/io.cc: Likewise.
+ * testsuite/std/time/month_weekday_last/io.cc: Likewise.
+ * testsuite/std/time/weekday/io.cc: Likewise.
+ * testsuite/std/time/weekday_indexed/io.cc: Likewise.
+ * testsuite/std/time/weekday_last/io.cc: Likewise.
+ * testsuite/std/time/year/io.cc: Likewise.
+ * testsuite/std/time/year_month/io.cc: Likewise.
+ * testsuite/std/time/year_month_day/io.cc: Likewise.
+ * testsuite/std/time/year_month_day_last/io.cc: Likewise.
+ * testsuite/std/time/year_month_weekday/io.cc: Likewise.
+ * testsuite/std/time/year_month_weekday_last/io.cc: Likewise.
+ * testsuite/std/time/zoned_time/io.cc: Likewise.
+
+2023-11-08 Jonathan Wakely <jwakely@redhat.com>
+
+ Backported from master:
+ 2023-10-21 Jonathan Wakely <jwakely@redhat.com>
+
+ * include/bits/basic_string.h (_M_init_local_buf()): New
+ function.
+ (_M_use_local_data()): Use _M_init_local_buf.
+ (basic_string(), basic_string(const Alloc&))
+ (basic_string(basic_string&&))
+ (basic_string(basic_string&&, const Alloc&)): Use
+ _M_init_local_buf instead of _M_use_local_data().
+ * include/bits/basic_string.tcc (swap(basic_string&))
+ (_M_construct(InIter, InIter, input_iterator_tag))
+ (_M_construct(InIter, InIter, forward_iterator_tag))
+ (_M_construct(size_type, CharT), reserve()): Likewise.
+
2023-11-06 Ian Lance Taylor <iant@golang.org>
PR libbacktrace/111315