[gcc r8-10446] Daily bump.

[GCC Administrator]

https://gcc.gnu.org/g:a46de9c7310c4927abc105e7d125c44e755bec60

commit r8-10446-ga46de9c7310c4927abc105e7d125c44e755bec60
Author: GCC Administrator <gccadmin@gcc.gnu.org>
Date:   Sat Sep 12 00:17:44 2020 +0000

    Daily bump.

Diff:
---
 gcc/DATESTAMP          |  2 +-
 libstdc++-v3/ChangeLog | 27 +++++++++++++++++++++++++++
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/gcc/DATESTAMP b/gcc/DATESTAMP
index 15fb79cba7d..c977cef8bc2 100644
--- a/gcc/DATESTAMP
+++ b/gcc/DATESTAMP
@@ -1 +1 @@
-20200911
+20200912
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 8cd063bfa9e..f477a26c38c 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,30 @@
+2020-09-11  Jonathan Wakely  <jwakely@redhat.com>
+
+	Backported from master:
+	2020-03-18  Jonathan Wakely  <jwakely@redhat.com>
+
+	PR libstdc++/94033
+	* include/std/type_traits (__is_nt_default_constructible_atom): Remove.
+	(__is_nt_default_constructible_impl): Remove.
+	(__is_nothrow_default_constructible_impl): Remove.
+	(__is_nt_constructible_impl): Add bool template parameter. Adjust
+	partial specializations.
+	(__is_nothrow_constructible_impl): Replace class template with alias
+	template.
+	(is_nothrow_default_constructible): Derive from alias template
+	__is_nothrow_constructible_impl instead of
+	__is_nothrow_default_constructible_impl.
+	* testsuite/20_util/is_nothrow_constructible/94003.cc: New test.
+	* testsuite/20_util/is_nothrow_default_constructible/96999.cc: New file.
+
+2020-09-11  Jonathan Wakely  <jwakely@redhat.com>
+
+	PR libstdc++/71960
+	* include/experimental/string_view (basic_string_view):
+	Enable debug assertions.
+	* include/std/string_view (basic_string_view):
+	Likewise.
+
 2020-08-10  Jonathan Wakely  <jwakely@redhat.com>
 
 	* src/c++17/Makefile.in: Remove unused file.