diff --git a/debian/changelog b/debian/changelog
index 3203df0c..3a7c0196 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -274,11 +274,42 @@ llvm-toolchain-snapshot (1:10~svn366440-1~exp1) experimental; urgency=medium
 
  -- Sylvestre Ledru <sylvestre@debian.org>  Thu, 18 Jul 2019 18:58:32 +0200
 
+llvm-toolchain-9 (1:9.0.1-11) unstable; urgency=medium
+
+  * Allow to build g++ 9 & 10 to fix a gcc build dependency (closes: #955144)
+    And disable thin lto on all archs
+    It needs gcc-8 after after 8 will reject the -flto=thin arg
+    And BOOTSTRAP_LLVM_ENABLE_LTO wil generate .so with llvm IR instead
+    of native code
+
+ -- Sylvestre Ledru <sylvestre@debian.org>  Tue, 31 Mar 2020 21:11:56 +0200
+
+llvm-toolchain-9 (1:9.0.1-10) unstable; urgency=medium
+
+  * debian/patches/947f9692440836dcb8d88b74b69dd379d85974ce.patch:
+    - cherry-pick upstream fix for glibc 2.31
+
+ -- Gianfranco Costamagna <locutusofborg@debian.org>  Sat, 07 Mar 2020 01:01:35 +0100
+
+llvm-toolchain-9 (1:9.0.1-9) unstable; urgency=medium
+
+  * Add patch to fix python3.8 test failures with deprecated cgi method, move
+    to new html parser
+
+ -- Gianfranco Costamagna <locutusofborg@debian.org>  Tue, 25 Feb 2020 15:28:58 +0100
+
 llvm-toolchain-9 (1:9.0.1-8) unstable; urgency=medium
 
+<<<<<<<
   * Add two new python autopkgtests to avoid regressions in the future
+=======
+  * Add two new python autopkgtests to avoid regressions in the future
+  * Fix m68k architecture
+  * Add Myself to uploaders
+  * Revert site-packages/dist-packages hacking mv, this is done upstream now
+>>>>>>>
 
- -- Gianfranco Costamagna <locutusofborg@debian.org>  Thu, 23 Jan 2020 10:08:27 +0100
+ -- Gianfranco Costamagna <locutusofborg@debian.org>  Thu, 23 Jan 2020 14:30:57 +0100
 
 llvm-toolchain-9 (1:9.0.1-7) unstable; urgency=medium
 
diff --git a/debian/control b/debian/control
index 253bec63..b0e4d24a 100644
--- a/debian/control
+++ b/debian/control
@@ -18,7 +18,7 @@ Build-Depends: debhelper (>= 9.0), cmake, chrpath, texinfo, sharutils,
     ocaml-findlib [amd64 arm64 armhf i386 ppc64el s390x],
     libctypes-ocaml-dev [amd64 arm64 armhf i386 ppc64el s390x],
     dh-exec, dh-ocaml [amd64 arm64 armhf i386 ppc64el s390x],
-    libpfm4-dev [linux-any], python3-setuptools, libz3-dev,
+    libpfm4-dev [linux-any], python3-setuptools, libz3-dev
 Build-Conflicts: oprofile, ocaml
 Standards-Version: 4.2.1
 Homepage: https://www.llvm.org/
diff --git a/debian/patches/series b/debian/patches/series
index 5cdb34d4..169ae904 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -139,6 +139,4 @@ no-z3.patch
 python3-shebang.patch
 print-lldb-path.patch
 no-cgi.patch
-d21664cce1db8debe2528f36b1fbd2b8af9c9401.patch
-
-0001-systemz-allow-configuring-default-SYSTEMZ_DEFAULT_AR.patch
+947f9692440836dcb8d88b74b69dd379d85974ce.patch
diff --git a/debian/qualify-clang.sh b/debian/qualify-clang.sh
index 6b7fb39d..55e5d585 100755
--- a/debian/qualify-clang.sh
+++ b/debian/qualify-clang.sh
@@ -700,6 +700,40 @@ int main(int argc, char **argv)
 clang-$VERSION -fsanitize=address foo.c -o foo -lc
 ./foo &> /dev/null || true
 
+echo '
+#include <pthread.h>
+#include <stdio.h>
+
+int Global;
+
+void *Thread1(void *x) {
+  Global++;
+  return NULL;
+}
+
+void *Thread2(void *x) {
+  Global--;
+  return NULL;
+}
+
+int main() {
+  pthread_t t[2];
+  pthread_create(&t[0], NULL, Thread1, NULL);
+  pthread_create(&t[1], NULL, Thread2, NULL);
+  pthread_join(t[0], NULL);
+  pthread_join(t[1], NULL);
+} ' > foo.c
+
+clang-$VERSION -o foo -fsanitize=thread -g -O1 foo.c
+if ! strings ./foo 2>&1 | grep -q "tsan"; then
+    echo "binary doesn't contain tsan code"
+    strings foo
+    exit 42
+fi
+if ! ./foo 2>&1 | grep -q "data race"; then
+    echo "sanitize=address is failing"
+    exit 42
+fi
 
 echo '
 class a {