diff --git a/debian/README b/debian/README
index 9065b72a..7e86a204 100644
--- a/debian/README
+++ b/debian/README
@@ -9,7 +9,7 @@ The current snapshot release is maintained in the "snapshot" branch.
 The easiest way to get all branches is probably to have one
 clone per version:
 
-for f in 8 9 snapshot; do
+for f in 8 9 10 snapshot; do
     git clone git@salsa.debian.org:pkg-llvm-team/llvm-toolchain.git -b $f $f
 done
 
@@ -57,7 +57,7 @@ branch at
   https://github.com/llvm/llvm-project/branches
 you should use,
 
-  $ sh 9/debian/orig-tar.sh release/9.x
+  $ sh 10/debian/orig-tar.sh release/10.x
 
 To retrieve a specific release candidate, you can pass the branch name as the
 first argument, and the tag rc number as the second argument. For example, to
@@ -65,11 +65,11 @@ get the 9.0.1 release candidate rc3 at
   https://github.com/llvm/llvm-project/tags
 you should use,
 
-  $ sh 9/debian/orig-tar.sh 9.0.1 rc3
+  $ sh 10/debian/orig-tar.sh 10.0.1 rc3
 
 For a stable release, the syntax is:
 
- $ sh 9/debian/orig-tar.sh 9.0.0
+ $ sh 10/debian/orig-tar.sh 10.0.0
 
 
 Additional maintainer scripts
diff --git a/debian/changelog b/debian/changelog
index 4b628498..4a3edf4c 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -28,7 +28,49 @@ llvm-toolchain-snapshot (1:11~++20200123111717+04fd2041561-1~exp1) experimental;
 
  -- Sylvestre Ledru <sylvestre@debian.org>  Thu, 23 Jan 2020 14:52:30 +0100
 
-llvm-toolchain-snapshot (1:10~++20191229111838+6991d5728f1-1~exp1) experimental; urgency=medium
+llvm-toolchain-10 (1:10.0.0~+rc2-1~exp1) experimental; urgency=medium
+
+  * Second RC release
+    - Should fix the s390x issue (reported upstream)
+    (Closes: #950900)
+  * Do not try to install hwasan_symbolize on armhf ppc64el
+    as it isn't built
+    (Closes: #950899)
+
+  [ Samuel Thibault ]
+  * hurd/hurd-cxx-paths.diff: Fix patch so it can be applied.
+  * clang-tools-X.Y.install.in: Do not try to install hwasan_symbolize on
+    hurd-any.
+
+ -- Sylvestre Ledru <sylvestre@debian.org>  Thu, 06 Feb 2020 10:37:39 +0100
+
+llvm-toolchain-10 (1:10.0.0~+rc1-1~exp1) experimental; urgency=medium
+
+  [ Gianfranco Costamagna ]
+  * fix lldb-10 -P path print (Closes: #945445)
+  * Fix lldb python installation path and symlinks
+  * Drop version constraint from libffi-dev library, satisfied since
+    old-old-stable
+
+  [ Sylvestre Ledru ]
+  * First RC release
+  * For now, disable ThinLTO usage because:
+      - LLVM_ENABLE_LTO doesn't work with gcc >= 9 (option not accepted)
+      - BOOTSTRAP_LLVM_ENABLE_LTO is producing some large binary
+        (uses llvm ir instead of binary code)
+        See https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=943623
+  * Thanks to this previous change, don't hardcode gcc 8
+
+ -- Sylvestre Ledru <sylvestre@debian.org>  Mon, 03 Feb 2020 10:30:50 +0100
+
+llvm-toolchain-10 (1:10~++20200121023453+de4b2a7fad6-1~exp1) experimental; urgency=medium
+
+  * Branch llvm-toolchain-10 into its own branch
+  * Merge recent 9 changes (python 3 and testsuite mostly)
+
+ -- Sylvestre Ledru <sylvestre@debian.org>  Tue, 21 Jan 2020 14:38:02 +0100
+
+llvm-toolchain-snapshot (1:10~+20191229111838+6991d5728f1-1~exp1) experimental; urgency=medium
 
   * experimental New snapshot release
   * Add a '+' in the version (as the old upload is high than the one without)
@@ -341,7 +383,7 @@ llvm-toolchain-9 (1:9.0.0-3~exp2) experimental; urgency=medium
     Disable fuzzer only for i386
   * Use stage2 files to build the doc. For some reasons, clang-tools-extra
     html generation stopped working
-  * Disable z3 when the version is tool old
+  * Disable z3 when the version is too old
 
  -- Sylvestre Ledru <sylvestre@debian.org>  Thu, 31 Oct 2019 00:29:09 +0100
 
diff --git a/debian/clang-tools-X.Y.install.in b/debian/clang-tools-X.Y.install.in
index 136fbdb2..823e3733 100644
--- a/debian/clang-tools-X.Y.install.in
+++ b/debian/clang-tools-X.Y.install.in
@@ -1,3 +1,5 @@
+#!/usr/bin/dh-exec
+
 usr/lib/llvm-@LLVM_VERSION@/bin/clang-check
 usr/lib/llvm-@LLVM_VERSION@/bin/clang-apply-replacements
 usr/lib/llvm-@LLVM_VERSION@/bin/clang-query
@@ -31,7 +33,7 @@ usr/lib/llvm-@LLVM_VERSION@/bin/pp-trace
 usr/lib/llvm-@LLVM_VERSION@/bin/clang-move
 usr/lib/llvm-@LLVM_VERSION@/bin/clang-offload-wrapper
 
-[!hurd-any] usr/lib/llvm-@LLVM_VERSION@/lib/clang/@LLVM_VERSION_FULL@/bin/hwasan_symbolize
+[!armhf !ppc64el !hurd-any] usr/lib/llvm-@LLVM_VERSION@/lib/clang/@LLVM_VERSION_FULL@/bin/hwasan_symbolize
 
 clang/tools/scan-build-@LLVM_VERSION@      usr/share/clang/
 clang/tools/scan-build-py-@LLVM_VERSION@      usr/share/clang/
diff --git a/debian/control b/debian/control
index a2ee9745..94b55a47 100644
--- a/debian/control
+++ b/debian/control
@@ -1,4 +1,4 @@
-Source: llvm-toolchain-snapshot
+Source: llvm-toolchain-10
 Section: devel
 Priority: optional
 Rules-Requires-Root: no
@@ -19,12 +19,11 @@ Build-Depends: debhelper (>= 9.0), cmake, chrpath, texinfo, sharutils,
     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,
-    g++-8 | g++-7 | g++-6 | g++-5 | g++-4.7
 Build-Conflicts: oprofile, ocaml
 Standards-Version: 4.2.1
 Homepage: https://www.llvm.org/
-Vcs-Git: https://salsa.debian.org/pkg-llvm-team/llvm-toolchain.git -b 9
-Vcs-Browser: https://salsa.debian.org/pkg-llvm-team/llvm-toolchain/tree/9
+Vcs-Git: https://salsa.debian.org/pkg-llvm-team/llvm-toolchain.git -b 10
+Vcs-Browser: https://salsa.debian.org/pkg-llvm-team/llvm-toolchain/tree/10
 
 # ------------- clang -------------
 
diff --git a/debian/qualify-clang.sh b/debian/qualify-clang.sh
index cbac741d..599695bb 100755
--- a/debian/qualify-clang.sh
+++ b/debian/qualify-clang.sh
@@ -9,8 +9,9 @@ VERSION=$(dpkg-parsechangelog | sed -rne "s,^Version: 1:([0-9]+).*,\1,p")
 DETAILED_VERSION=$(dpkg-parsechangelog |  sed -rne "s,^Version: 1:([0-9.]+)(~|-)(.*),\1\2\3,p")
 DEB_HOST_ARCH=$(dpkg-architecture -qDEB_HOST_ARCH)
 
-LIST="libomp5-${VERSION}_${DETAILED_VERSION}_amd64.deb libomp-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb lldb-${VERSION}_${DETAILED_VERSION}_amd64.deb python3-lldb-${VERSION}_${DETAILED_VERSION}_amd64.deb libllvm${VERSION}_${DETAILED_VERSION}_amd64.deb llvm-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb liblldb-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb  libclang1-${VERSION}_${DETAILED_VERSION}_amd64.deb  libclang-common-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb  llvm-${VERSION}_${DETAILED_VERSION}_amd64.deb  liblldb-${VERSION}_${DETAILED_VERSION}_amd64.deb  llvm-${VERSION}-runtime_${DETAILED_VERSION}_amd64.deb lld-${VERSION}_${DETAILED_VERSION}_amd64.deb libfuzzer-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb libclang-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb libc++-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb libc++abi-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb libc++1-${VERSION}_${DETAILED_VERSION}_amd64.deb libc++abi1-${VERSION}_${DETAILED_VERSION}_amd64.deb clang-${VERSION}_${DETAILED_VERSION}_amd64.deb llvm-${VERSION}-tools_${DETAILED_VERSION}_amd64.deb clang-tools-${VERSION}_${DETAILED_VERSION}_amd64.deb clangd-${VERSION}_${DETAILED_VERSION}_amd64.deb clang-${VERSION}-dbgsym_${DETAILED_VERSION}_amd64.deb libclang1-${VERSION}-dbgsym_${DETAILED_VERSION}_amd64.deb libclang-cpp${VERSION}_${DETAILED_VERSION}_amd64.deb  clang-tidy-${VERSION}_${DETAILED_VERSION}_amd64.deb"
+LIST="libomp5-${VERSION}_${DETAILED_VERSION}_amd64.deb libomp-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb lldb-${VERSION}_${DETAILED_VERSION}_amd64.deb python3-lldb-${VERSION}_${DETAILED_VERSION}_amd64.deb libllvm${VERSION}_${DETAILED_VERSION}_amd64.deb llvm-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb liblldb-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb  libclang1-${VERSION}_${DETAILED_VERSION}_amd64.deb  libclang-common-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb  llvm-${VERSION}_${DETAILED_VERSION}_amd64.deb  liblldb-${VERSION}_${DETAILED_VERSION}_amd64.deb  llvm-${VERSION}-runtime_${DETAILED_VERSION}_amd64.deb lld-${VERSION}_${DETAILED_VERSION}_amd64.deb libfuzzer-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb libclang-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb libc++-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb libc++abi-${VERSION}-dev_${DETAILED_VERSION}_amd64.deb libc++1-${VERSION}_${DETAILED_VERSION}_amd64.deb libc++abi1-${VERSION}_${DETAILED_VERSION}_amd64.deb clang-${VERSION}_${DETAILED_VERSION}_amd64.deb llvm-${VERSION}-tools_${DETAILED_VERSION}_amd64.deb clang-tools-${VERSION}_${DETAILED_VERSION}_amd64.deb clangd-${VERSION}_${DETAILED_VERSION}_amd64.deb clang-${VERSION}-dbgsym_${DETAILED_VERSION}_amd64.deb libclang1-${VERSION}-dbgsym_${DETAILED_VERSION}_amd64.deb libclang-cpp${VERSION}_${DETAILED_VERSION}_amd64.deb"
 echo "To install everything:"
+echo "sudo apt --purge remove 'libomp5-*' 'libc++*dev' 'libc++*'"
 echo "sudo dpkg -i $LIST"
 L=""
 for f in $LIST; do
diff --git a/debian/rules b/debian/rules
index b3ff0677..2069f305 100755
--- a/debian/rules
+++ b/debian/rules
@@ -75,15 +75,6 @@ ifneq ($(shell dpkg-vendor --derives-from Ubuntu && echo yes),yes)
 endif
 endif
 
-FORCE_NOT_GCC_9_DISTRO := eoan focal bullseye sid
-ifneq (,$(filter $(DISTRO),$(FORCE_NOT_GCC_9_DISTRO)))
-# Force gcc before 9 (gcc 8 on Debian unstable) because it causes
-# huge increase of the size of the .deb (because of .a and .so) and issues in the libs
-	GCC_VERSION := 8
-endif
-
-
-
 export CC=gcc-$(GCC_VERSION)
 export CXX=g++-$(GCC_VERSION)
 
@@ -244,7 +235,13 @@ ifneq (,$(filter $(DEB_HOST_ARCH),$(BINUTILS_GOLD_ARCHS)))
 # armhf is not yet quite ready for Thin, it FTBFS
 # see https://buildd.debian.org/status/fetch.php?pkg=llvm-toolchain-8&arch=armhf&ver=1%3A8.0.1%7E%2Brc2-1%7Eexp1&stamp=1560334266&raw=0
 ifeq (,$(filter $(DEB_HOST_ARCH), armhf))
-	CMAKE_EXTRA += -DLLVM_ENABLE_LTO="Thin"
+# Use BOOTSTRAP_LLVM_ENABLE_LTO to make sure that it isn't used
+# when running stage1 with gcc
+# For now, disable ThinLTO usage because:
+# * LLVM_ENABLE_LTO doesn't work with gcc >= 9 (option not accepted)
+# * BOOTSTRAP_LLVM_ENABLE_LTO is producing some large binary
+#   See https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=943623
+#	CMAKE_EXTRA += -DBOOTSTRAP_LLVM_ENABLE_LTO="Thin"
 endif
 endif
 endif
@@ -299,7 +296,7 @@ preconfigure:
 	done
 
 	# Make install file executable for dh-exec
-	chmod +x debian/llvm-$(LLVM_VERSION)-dev.install
+	chmod +x debian/llvm-$(LLVM_VERSION)-dev.install debian/clang-tools-$(LLVM_VERSION).install
 
 	# DH doesn't support the [power ...] in install on Ubuntu trusty
 	# fails with cp: cannot stat 'debian/tmp/[!powerpc': No such file or directory