diff --git a/debian/changelog b/debian/changelog
index cc44a20d..21361952 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,26 @@
+llvm-toolchain-12 (1:12.0.1-11) UNRELEASED; urgency=medium
+
+  * evolve llvm build configuration in rules to leverage the two stage build
+    with runtimes support whereby the resulting stage2 (final) compiler is used
+    to build the stage2 (final) runtimes as part of a single monolithic build
+  * the stage2 runtimes build now includes compiler-rt, libcxx and libcxxabi as
+    well as libunwind and openmp where supported. Additionally, legacy
+    corresponding standalone build targets are removed from the rules file
+  * patch openmp build to include required runtimes as dependencies to build
+    targets so they are built first when included as part of a runtimes build
+    since openmp can depend on them
+  * patch libclc build to set rpath for prepare_builtins build utility to find
+    correct stage2 libs at runtime when executed as part of a build
+  * patch libcxx build so that if libatomic is found, only link it if libgcc is
+    the rtlib
+  * patch compiler-rt build to suppress xray and testing warns when not enabled
+  * patch llvm linker detection to account for vendor being prepended to lld
+    version string
+  * remove several existing patches incorporating workarounds no longer required
+    by the modified build configuration
+
+ -- Erik Maciejewski <mr.emacski@gmail.com>  Wed, 06 Oct 2021 01:25:08 -0700
+
 llvm-toolchain-12 (1:12.0.1-10) UNRELEASED; urgency=medium
 
   * If parallel is not set in DEB_BUILD_OPTIONS, use nproc
diff --git a/debian/control b/debian/control
index 9294f7d4..6e60288b 100644
--- a/debian/control
+++ b/debian/control
@@ -6,6 +6,7 @@ Maintainer: LLVM Packaging Team <pkg-llvm-team@lists.alioth.debian.org>
 Uploaders: Sylvestre Ledru <sylvestre@debian.org>, Gianfranco Costamagna <locutusofborg@debian.org>
 Build-Depends: debhelper (>= 9.0), cmake, ninja-build,
     chrpath, texinfo, sharutils,
+    libelf-dev,
     libffi-dev,
     lsb-release, patchutils, diffstat, xz-utils, python3-dev,
     libedit-dev, libncurses5-dev, swig, python3-six, python3-sphinx (>= 1.3.6),
diff --git a/debian/patches/compilerrt-fix-warn-xray-testing.diff b/debian/patches/compilerrt-fix-warn-xray-testing.diff
new file mode 100644
index 00000000..38babc96
--- /dev/null
+++ b/debian/patches/compilerrt-fix-warn-xray-testing.diff
@@ -0,0 +1,33 @@
+suppress warnings for xray and testing when not enabled
+Index: llvm-toolchain-12_12.0.1/compiler-rt/cmake/Modules/CompilerRTUtils.cmake
+===================================================================
+--- llvm-toolchain-12_12.0.1.orig/compiler-rt/cmake/Modules/CompilerRTUtils.cmake
++++ llvm-toolchain-12_12.0.1/compiler-rt/cmake/Modules/CompilerRTUtils.cmake
+@@ -242,15 +242,15 @@ macro(load_llvm_config)
+ 
+     # Detect if we have the LLVMXRay and TestingSupport library installed and
+     # available from llvm-config.
++    set(COMPILER_RT_HAS_LLVMXRAY FALSE)
+     execute_process(
+       COMMAND ${LLVM_CONFIG_PATH} "--ldflags" "--libs" "xray"
+       RESULT_VARIABLE HAD_ERROR
+       OUTPUT_VARIABLE CONFIG_OUTPUT
+       ERROR_QUIET)
+-    if (HAD_ERROR)
++    if (HAD_ERROR AND COMPILER_RT_BUILD_XRAY)
+       message(WARNING "llvm-config finding xray failed with status ${HAD_ERROR}")
+-      set(COMPILER_RT_HAS_LLVMXRAY FALSE)
+-    else()
++    elseif(COMPILER_RT_BUILD_XRAY)
+       string(REGEX REPLACE "[ \t]*[\r\n]+[ \t]*" ";" CONFIG_OUTPUT ${CONFIG_OUTPUT})
+       list(GET CONFIG_OUTPUT 0 LDFLAGS)
+       list(GET CONFIG_OUTPUT 1 LIBLIST)
+@@ -267,7 +267,7 @@ macro(load_llvm_config)
+       RESULT_VARIABLE HAD_ERROR
+       OUTPUT_VARIABLE CONFIG_OUTPUT
+       ERROR_QUIET)
+-    if (HAD_ERROR)
++    if (HAD_ERROR AND COMPILER_RT_INCLUDE_TESTS)
+       message(WARNING "llvm-config finding testingsupport failed with status ${HAD_ERROR}")
+     elseif(COMPILER_RT_INCLUDE_TESTS)
+       string(REGEX REPLACE "[ \t]*[\r\n]+[ \t]*" ";" CONFIG_OUTPUT ${CONFIG_OUTPUT})
diff --git a/debian/patches/fix-llvm-config-obj-src-root.patch b/debian/patches/fix-llvm-config-obj-src-root.patch
deleted file mode 100644
index 2981e9b7..00000000
--- a/debian/patches/fix-llvm-config-obj-src-root.patch
+++ /dev/null
@@ -1,20 +0,0 @@
----
- tools/llvm-config/llvm-config.cpp |    4 ++--
- 1 file changed, 2 insertions(+), 2 deletions(-)
-
-Index: llvm-toolchain-snapshot_11~++20200326111000+4673699a470/llvm/tools/llvm-config/llvm-config.cpp
-===================================================================
---- llvm-toolchain-snapshot_11~++20200326111000+4673699a470.orig/llvm/tools/llvm-config/llvm-config.cpp
-+++ llvm-toolchain-snapshot_11~++20200326111000+4673699a470/llvm/tools/llvm-config/llvm-config.cpp
-@@ -561,9 +561,9 @@ int main(int argc, char **argv) {
-       } else if (Arg == "--shared-mode") {
-         PrintSharedMode = true;
-       } else if (Arg == "--obj-root") {
--        OS << ActivePrefix << '\n';
-+        OS << ActivePrefix << "/build/" << '\n';
-       } else if (Arg == "--src-root") {
--        OS << LLVM_SRC_ROOT << '\n';
-+        OS << ActivePrefix << "/build/" << '\n';
-       } else if (Arg == "--ignore-libllvm") {
-         LinkDyLib = false;
-         LinkMode = BuiltSharedLibs ? LinkModeShared : LinkModeAuto;
diff --git a/debian/patches/libclc-fix-prepare_builtins-rpath.diff b/debian/patches/libclc-fix-prepare_builtins-rpath.diff
new file mode 100644
index 00000000..c1f87571
--- /dev/null
+++ b/debian/patches/libclc-fix-prepare_builtins-rpath.diff
@@ -0,0 +1,16 @@
+set rpath for prepare_builtins build utility to find correct stage2
+libs at runtime when executed as part of a build
+Index: llvm-toolchain-12_12.0.1/libclc/CMakeLists.txt
+===================================================================
+--- llvm-toolchain-12_12.0.1.orig/libclc/CMakeLists.txt
++++ llvm-toolchain-12_12.0.1/libclc/CMakeLists.txt
+@@ -139,6 +139,9 @@ target_compile_options( prepare_builtins
+ target_compile_definitions( prepare_builtins PRIVATE ${LLVM_VERSION_DEFINE} )
+ target_link_libraries( prepare_builtins PRIVATE ${LLVM_LIBS} )
+ target_link_libraries( prepare_builtins PRIVATE ${LLVM_SYSTEM_LIBS} )
++set_target_properties( prepare_builtins
++                       PROPERTIES INSTALL_RPATH "${LLVM_LIBDIR}"
++                       BUILD_WITH_INSTALL_RPATH "ON")
+ 
+ # Setup arch devices
+ set( r600--_devices cedar cypress barts cayman )
diff --git a/debian/patches/libcxx-libatomic-only-with-gcc-rtlib.diff b/debian/patches/libcxx-libatomic-only-with-gcc-rtlib.diff
new file mode 100644
index 00000000..41662966
--- /dev/null
+++ b/debian/patches/libcxx-libatomic-only-with-gcc-rtlib.diff
@@ -0,0 +1,24 @@
+if libatomic is found only link it if libgcc is the rtlib
+Index: llvm-toolchain-12_12.0.1/libcxx/CMakeLists.txt
+===================================================================
+--- llvm-toolchain-12_12.0.1.orig/libcxx/CMakeLists.txt
++++ llvm-toolchain-12_12.0.1/libcxx/CMakeLists.txt
+@@ -756,12 +756,14 @@ function(cxx_link_system_libraries targe
+     endif()
+   elseif (LIBCXX_HAS_GCC_LIB)
+     target_link_libraries(${target} PRIVATE gcc)
++    if (LIBCXX_HAS_ATOMIC_LIB)
++      target_link_libraries(${target} PRIVATE atomic)
++    endif()
+   elseif (LIBCXX_HAS_GCC_S_LIB)
+     target_link_libraries(${target} PRIVATE gcc_s)
+-  endif()
+-
+-  if (LIBCXX_HAS_ATOMIC_LIB)
+-    target_link_libraries(${target} PRIVATE atomic)
++    if (LIBCXX_HAS_ATOMIC_LIB)
++      target_link_libraries(${target} PRIVATE atomic)
++    endif()
+   endif()
+ 
+   if (MINGW)
diff --git a/debian/patches/lld-use-link-atomic-i386.diff b/debian/patches/lld-use-link-atomic-i386.diff
deleted file mode 100644
index 02cca874..00000000
--- a/debian/patches/lld-use-link-atomic-i386.diff
+++ /dev/null
@@ -1,32 +0,0 @@
-Index: llvm-toolchain-snapshot_12~++20201021061106+4b7dafd9046/lld/tools/lld/CMakeLists.txt
-===================================================================
---- llvm-toolchain-snapshot_12~++20201021061106+4b7dafd9046.orig/lld/tools/lld/CMakeLists.txt
-+++ llvm-toolchain-snapshot_12~++20201021061106+4b7dafd9046/lld/tools/lld/CMakeLists.txt
-@@ -1,10 +1,18 @@
-+set(LLD_ATOMIC_LIB "")
-+
- set(LLVM_LINK_COMPONENTS
-   Support
-   )
- 
-+if(CMAKE_HOST_SYSTEM_PROCESSOR MATCHES "i386" OR
-+    CMAKE_HOST_SYSTEM_PROCESSOR MATCHES "i686" OR
-+    CMAKE_SYSTEM_PROCESSOR STREQUAL "x86_64" OR CMAKE_SYSTEM_PROCESSOR STREQUAL "amd64"
-+  )
-+  list(APPEND LLD_ATOMIC_LIB "atomic")
-+endif()
-+
- add_lld_tool(lld
-   lld.cpp
--
-   SUPPORT_PLUGINS
-   )
- export_executable_symbols_for_plugins(lld)
-@@ -18,6 +26,7 @@ target_link_libraries(lld
-   lldMachO2
-   lldMinGW
-   lldWasm
-+  ${LLD_ATOMIC_LIB}
-   )
- 
- install(TARGETS lld
diff --git a/debian/patches/llvm-fix-lld-linker-check.diff b/debian/patches/llvm-fix-lld-linker-check.diff
new file mode 100644
index 00000000..bad28992
--- /dev/null
+++ b/debian/patches/llvm-fix-lld-linker-check.diff
@@ -0,0 +1,15 @@
+remove regex anchor in lld linker detection to account for vendor, if
+specified, being prepended to lld version string
+Index: llvm-toolchain-12_12.0.1/llvm/cmake/modules/AddLLVM.cmake
+===================================================================
+--- llvm-toolchain-12_12.0.1.orig/llvm/cmake/modules/AddLLVM.cmake
++++ llvm-toolchain-12_12.0.1/llvm/cmake/modules/AddLLVM.cmake
+@@ -196,7 +196,7 @@ if (NOT DEFINED LLVM_LINKER_DETECTED)
+       set(LLVM_LINKER_DETECTED YES CACHE INTERNAL "")
+       set(LLVM_LINKER_IS_GOLD YES CACHE INTERNAL "")
+       message(STATUS "Linker detection: GNU Gold")
+-    elseif("${stdout}" MATCHES "^LLD")
++    elseif("${stdout}" MATCHES "LLD")
+       set(LLVM_LINKER_DETECTED YES CACHE INTERNAL "")
+       set(LLVM_LINKER_IS_LLD YES CACHE INTERNAL "")
+       message(STATUS "Linker detection: LLD")
diff --git a/debian/patches/openmp-fix-runtimes-build.diff b/debian/patches/openmp-fix-runtimes-build.diff
new file mode 100644
index 00000000..b8d20cd0
--- /dev/null
+++ b/debian/patches/openmp-fix-runtimes-build.diff
@@ -0,0 +1,162 @@
+include required runtimes as dependencies to openmp targets to make sure
+they are built first when included as part of a runtimes build since openmp
+can depend on them
+Index: llvm-toolchain-12_12.0.1/llvm/runtimes/CMakeLists.txt
+===================================================================
+--- llvm-toolchain-12_12.0.1.orig/llvm/runtimes/CMakeLists.txt
++++ llvm-toolchain-12_12.0.1/llvm/runtimes/CMakeLists.txt
+@@ -236,6 +236,7 @@ function(runtime_default_target)
+                                       -DLLVM_DEFAULT_TARGET_TRIPLE=${TARGET_TRIPLE}
+                                       -DLLVM_ENABLE_PROJECTS_USED=${LLVM_ENABLE_PROJECTS_USED}
+                                       -DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=${LLVM_ENABLE_PER_TARGET_RUNTIME_DIR_default}
++                                      -DCMAKE_SYSTEM_PROCESSOR=${CMAKE_SYSTEM_PROCESSOR}
+                                       -DCMAKE_C_COMPILER_TARGET=${TARGET_TRIPLE}
+                                       -DCMAKE_CXX_COMPILER_TARGET=${TARGET_TRIPLE}
+                                       -DCMAKE_ASM_COMPILER_TARGET=${TARGET_TRIPLE}
+@@ -440,7 +441,7 @@ if(runtimes)
+     # build directory cannot find the C++ headers in certain configurations.
+     # I need to build a mechanism for runtime projects to provide CMake code
+     # that executes at LLVM configuration time to handle this case.
+-    add_dependencies(clang-bootstrap-deps runtimes-configure)
++    #add_dependencies(clang-bootstrap-deps runtimes-configure)
+     # We need to add the runtimes as a dependency because compiler-rt can be
+     # built as part of runtimes and we need the profile runtime for PGO
+     add_dependencies(clang-bootstrap-deps runtimes)
+Index: llvm-toolchain-12_12.0.1/openmp/CMakeLists.txt
+===================================================================
+--- llvm-toolchain-12_12.0.1.orig/openmp/CMakeLists.txt
++++ llvm-toolchain-12_12.0.1/openmp/CMakeLists.txt
+@@ -83,6 +83,28 @@ option(OPENMP_ENABLE_LIBOMPTARGET_PROFIL
+        ${ENABLE_LIBOMPTARGET})
+ option(OPENMP_ENABLE_LIBOMP_PROFILING "Enable time profiling for libomp." OFF)
+ 
++option(OPENMP_USE_LLVM_UNWINDER "Build and use the LLVM unwinder" OFF)
++
++option(LIBOMP_ENABLE_RTTI "Enabling RTTI forces libomp to be a c++ lib" ${LLVM_ENABLE_RTTI})
++
++macro(add_runtimes_build_depends_if_needed target)
++  if(RUNTIMES_BUILD)
++    # required for rtti and libomp/libomptarget profiling if enabled
++    add_dependencies(${target} cxx-headers cxxabi_static cxx_static cxxabi_shared cxx_shared)
++    if(OPENMP_USE_LLVM_UNWINDER AND (NOT target STREQUAL "omp" AND NOT LIBOMP_ENABLE_RTTI))
++      add_dependencies(${target} unwind_static unwind_shared)
++      get_target_property(target_link_flags ${target} LINK_FLAGS)
++      set(runtimes_link_flags "-lunwind")
++      if(target_link_flags)
++        set(runtimes_link_flags "${target_link_flags} -lunwind")
++      endif()
++      set_target_properties(${target}
++        PROPERTIES
++        LINK_FLAGS "${runtimes_link_flags}")
++    endif()
++  endif()
++endmacro()
++
+ # Build host runtime library, after LIBOMPTARGET variables are set since they are needed
+ # to enable time profiling support in the OpenMP runtime.
+ add_subdirectory(runtime)
+Index: llvm-toolchain-12_12.0.1/openmp/cmake/HandleOpenMPOptions.cmake
+===================================================================
+--- llvm-toolchain-12_12.0.1.orig/openmp/cmake/HandleOpenMPOptions.cmake
++++ llvm-toolchain-12_12.0.1/openmp/cmake/HandleOpenMPOptions.cmake
+@@ -29,7 +29,8 @@ append_if(OPENMP_HAVE_WNO_EXTRA_FLAG "-W
+ append_if(OPENMP_HAVE_WNO_PEDANTIC_FLAG "-Wno-pedantic" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
+ append_if(OPENMP_HAVE_WNO_MAYBE_UNINITIALIZED_FLAG "-Wno-maybe-uninitialized" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
+ 
+-append_if(OPENMP_HAVE_STD_GNUPP14_FLAG "-std=gnu++14" CMAKE_CXX_FLAGS)
+-if (NOT OPENMP_HAVE_STD_GNUPP14_FLAG)
+-  append_if(OPENMP_HAVE_STD_CPP14_FLAG "-std=c++14" CMAKE_CXX_FLAGS)
++# prefer c++14 over gnu++14?
++append_if(OPENMP_HAVE_STD_CPP14_FLAG "-std=c++14" CMAKE_CXX_FLAGS)
++if (NOT OPENMP_HAVE_STD_CPP14_FLAG)
++  append_if(OPENMP_HAVE_STD_GNUPP14_FLAG "-std=gnu++14" CMAKE_CXX_FLAGS)
+ endif()
+Index: llvm-toolchain-12_12.0.1/openmp/libomptarget/plugins/CMakeLists.txt
+===================================================================
+--- llvm-toolchain-12_12.0.1.orig/openmp/libomptarget/plugins/CMakeLists.txt
++++ llvm-toolchain-12_12.0.1/openmp/libomptarget/plugins/CMakeLists.txt
+@@ -36,6 +36,8 @@ if(CMAKE_SYSTEM_PROCESSOR MATCHES "${tma
+       add_library("omptarget.rtl.${tmachine_libname}" SHARED
+         ${CMAKE_CURRENT_SOURCE_DIR}/../generic-elf-64bit/src/rtl.cpp)
+ 
++      add_runtimes_build_depends_if_needed("omptarget.rtl.${tmachine_libname}")
++
+       # Install plugin under the lib destination folder.
+       install(TARGETS "omptarget.rtl.${tmachine_libname}"
+         LIBRARY DESTINATION "${OPENMP_INSTALL_LIBDIR}")
+Index: llvm-toolchain-12_12.0.1/openmp/libomptarget/plugins/cuda/CMakeLists.txt
+===================================================================
+--- llvm-toolchain-12_12.0.1.orig/openmp/libomptarget/plugins/cuda/CMakeLists.txt
++++ llvm-toolchain-12_12.0.1/openmp/libomptarget/plugins/cuda/CMakeLists.txt
+@@ -44,6 +44,8 @@ else()
+   set (LIBOMPTARGET_DEP_LIBRARIES ${CMAKE_DL_LIBS})
+ endif()
+ 
++add_runtimes_build_depends_if_needed(omptarget.rtl.cuda)
++
+ # Install plugin under the lib destination folder.
+ install(TARGETS omptarget.rtl.cuda LIBRARY DESTINATION "${OPENMP_INSTALL_LIBDIR}")
+ 
+Index: llvm-toolchain-12_12.0.1/openmp/libomptarget/src/CMakeLists.txt
+===================================================================
+--- llvm-toolchain-12_12.0.1.orig/openmp/libomptarget/src/CMakeLists.txt
++++ llvm-toolchain-12_12.0.1/openmp/libomptarget/src/CMakeLists.txt
+@@ -48,6 +48,8 @@ set_target_properties(omptarget
+   PROPERTIES
+   LIBRARY_OUTPUT_DIRECTORY ${LIBOMPTARGET_LIBRARY_DIR})
+ 
++add_runtimes_build_depends_if_needed(omptarget)
++
+ # Install libomptarget under the lib destination folder.
+ install(TARGETS omptarget LIBRARY COMPONENT omptarget
+   DESTINATION "${OPENMP_INSTALL_LIBDIR}")
+Index: llvm-toolchain-12_12.0.1/openmp/runtime/CMakeLists.txt
+===================================================================
+--- llvm-toolchain-12_12.0.1.orig/openmp/runtime/CMakeLists.txt
++++ llvm-toolchain-12_12.0.1/openmp/runtime/CMakeLists.txt
+@@ -287,6 +287,10 @@ if(LIBOMP_STATS)
+   set(LIBOMP_USE_STDCPPLIB TRUE)
+ endif()
+ 
++if(LIBOMP_ENABLE_RTTI)
++  set(LIBOMP_USE_STDCPPLIB TRUE)
++endif()
++
+ # Shared library can be switched to a static library
+ set(LIBOMP_ENABLE_SHARED TRUE CACHE BOOL
+   "Shared library instead of static library?")
+Index: llvm-toolchain-12_12.0.1/openmp/runtime/src/CMakeLists.txt
+===================================================================
+--- llvm-toolchain-12_12.0.1.orig/openmp/runtime/src/CMakeLists.txt
++++ llvm-toolchain-12_12.0.1/openmp/runtime/src/CMakeLists.txt
+@@ -134,6 +134,7 @@ endif()
+ if(NOT ${LIBOMP_USE_STDCPPLIB})
+   set(LIBOMP_LINKER_LANGUAGE C)
+   set(CMAKE_CXX_IMPLICIT_LINK_LIBRARIES)
++  set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nostdlib++")
+ else()
+   set(LIBOMP_LINKER_LANGUAGE CXX)
+ endif()
+@@ -162,6 +163,8 @@ set_target_properties(omp PROPERTIES
+   LINKER_LANGUAGE ${LIBOMP_LINKER_LANGUAGE}
+ )
+ 
++add_runtimes_build_depends_if_needed(omp)
++
+ # Get the library's location within the build tree for the unit tester
+ if(NOT WIN32)
+   get_target_property(LIBOMP_LIBRARY_DIR omp LIBRARY_OUTPUT_DIRECTORY)
+Index: llvm-toolchain-12_12.0.1/openmp/tools/archer/CMakeLists.txt
+===================================================================
+--- llvm-toolchain-12_12.0.1.orig/openmp/tools/archer/CMakeLists.txt
++++ llvm-toolchain-12_12.0.1/openmp/tools/archer/CMakeLists.txt
+@@ -14,6 +14,9 @@ if(LIBOMP_OMPT_SUPPORT)
+   add_library(archer SHARED ompt-tsan.cpp)
+   add_library(archer_static STATIC ompt-tsan.cpp)
+ 
++  add_runtimes_build_depends_if_needed(archer)
++  add_runtimes_build_depends_if_needed(archer_static)
++
+   install(TARGETS archer archer_static
+     LIBRARY DESTINATION ${OPENMP_INSTALL_LIBDIR}
+     ARCHIVE DESTINATION ${OPENMP_INSTALL_LIBDIR})
diff --git a/debian/patches/series b/debian/patches/series
index b872895b..62f77466 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -27,7 +27,6 @@ do-not-fail-on-unexpected-pass.diff
 disable-display-PASS-UNSUPPORTED-XFAIL.diff
 
 # llvm-config
-fix-llvm-config-obj-src-root.patch
 0001-llvm-cmake-resolve-symlinks-in-LLVMConfig.cmake.patch
 
 # Lib names
@@ -126,9 +125,6 @@ risc/clang-riscv64-multiarch.diff
 sparc/sparc-D98574-clang-def.patch
 sparc/sparc-D98575-compiler-rt.patch
 
-# Compiler-rt - workaround
-workaround-bug-42994-use-linker.diff
-
 # bug 939472
 #try-to-unbreak-thinlto.diff
 #D67877-cmake-clang-example.patch
@@ -138,7 +134,6 @@ x86-fuzzer.patch
 python3-shebang.patch
 print-lldb-path.patch
 libcxx-armhf-ftbfs.diff
-lld-use-link-atomic-i386.diff
 #bring-reporter-back.patch
 D99501-ignore-lto-auto.diff
 scan-build-py-fix-analyze-path.diff
@@ -146,3 +141,8 @@ scan-build-py-fix-default-bin.diff
 
 libclc-llvm-spirv.diff
 omp-riscv64.patch
+llvm-fix-lld-linker-check.diff
+compilerrt-fix-warn-xray-testing.diff
+openmp-fix-runtimes-build.diff
+libclc-fix-prepare_builtins-rpath.diff
+libcxx-libatomic-only-with-gcc-rtlib.diff
diff --git a/debian/patches/symbolizer-path.diff b/debian/patches/symbolizer-path.diff
index 3eaaaf84..69caab13 100644
--- a/debian/patches/symbolizer-path.diff
+++ b/debian/patches/symbolizer-path.diff
@@ -1,7 +1,7 @@
-Index: llvm-toolchain-snapshot_11~++20200326111000+4673699a470/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp
+Index: llvm-toolchain-12_12.0.1/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp
 ===================================================================
---- llvm-toolchain-snapshot_11~++20200326111000+4673699a470.orig/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp
-+++ llvm-toolchain-snapshot_11~++20200326111000+4673699a470/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp
+--- llvm-toolchain-12_12.0.1.orig/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp
++++ llvm-toolchain-12_12.0.1/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp
 @@ -25,6 +25,10 @@
  #include "sanitizer_symbolizer_internal.h"
  #include "sanitizer_symbolizer_libbacktrace.h"
@@ -13,7 +13,7 @@ Index: llvm-toolchain-snapshot_11~++20200326111000+4673699a470/compiler-rt/lib/s
  
  #include <dlfcn.h>   // for dlsym()
  #include <errno.h>
-@@ -428,7 +432,7 @@ static SymbolizerTool *ChooseExternalSym
+@@ -433,7 +437,7 @@ static SymbolizerTool *ChooseExternalSym
      return new(*allocator) AtosSymbolizer(found_path, allocator);
    }
  #endif  // SANITIZER_MAC
@@ -22,3 +22,15 @@ Index: llvm-toolchain-snapshot_11~++20200326111000+4673699a470/compiler-rt/lib/s
      VReport(2, "Using llvm-symbolizer found at: %s\n", found_path);
      return new(*allocator) LLVMSymbolizer(found_path, allocator);
    }
+Index: llvm-toolchain-12_12.0.1/compiler-rt/lib/sanitizer_common/CMakeLists.txt
+===================================================================
+--- llvm-toolchain-12_12.0.1.orig/compiler-rt/lib/sanitizer_common/CMakeLists.txt
++++ llvm-toolchain-12_12.0.1/compiler-rt/lib/sanitizer_common/CMakeLists.txt
+@@ -195,6 +195,7 @@ set(SANITIZER_IMPL_HEADERS
+   )
+ 
+ include_directories(..)
++include_directories(${LLVM_INCLUDE_DIR})
+ 
+ set(SANITIZER_COMMON_DEFINITIONS
+   HAVE_RPC_XDR_H=${HAVE_RPC_XDR_H})
diff --git a/debian/patches/workaround-bug-42994-use-linker.diff b/debian/patches/workaround-bug-42994-use-linker.diff
deleted file mode 100644
index 3d87717d..00000000
--- a/debian/patches/workaround-bug-42994-use-linker.diff
+++ /dev/null
@@ -1,34 +0,0 @@
-Index: llvm-toolchain-snapshot_11~++20200326111000+4673699a470/compiler-rt/lib/hwasan/CMakeLists.txt
-===================================================================
---- llvm-toolchain-snapshot_11~++20200326111000+4673699a470.orig/compiler-rt/lib/hwasan/CMakeLists.txt
-+++ llvm-toolchain-snapshot_11~++20200326111000+4673699a470/compiler-rt/lib/hwasan/CMakeLists.txt
-@@ -43,9 +43,9 @@ append_list_if(COMPILER_RT_HWASAN_WITH_I
- 
- set(HWASAN_RTL_CFLAGS ${SANITIZER_COMMON_CFLAGS})
- append_rtti_flag(OFF HWASAN_RTL_CFLAGS)
--append_list_if(COMPILER_RT_HAS_FPIC_FLAG -fPIC HWASAN_RTL_CFLAGS)
-+append_list_if(COMPILER_RT_HAS_FPIC_FLAG -fPIC -fuse-ld=gold HWASAN_RTL_CFLAGS)
- # Prevent clang from generating libc calls.
--append_list_if(COMPILER_RT_HAS_FFREESTANDING_FLAG -ffreestanding HWASAN_RTL_CFLAGS)
-+append_list_if(COMPILER_RT_HAS_FFREESTANDING_FLAG -ffreestanding -fuse-ld=gold HWASAN_RTL_CFLAGS)
- 
- set(HWASAN_DYNAMIC_LINK_FLAGS ${SANITIZER_COMMON_LINK_FLAGS})
- 
-@@ -57,7 +57,7 @@ if(ANDROID)
-   endif()
- endif()
- 
--set(HWASAN_DYNAMIC_CFLAGS ${HWASAN_RTL_CFLAGS})
-+set(HWASAN_DYNAMIC_CFLAGS ${HWASAN_RTL_CFLAGS} -fuse-ld=gold)
- append_list_if(COMPILER_RT_HAS_FTLS_MODEL_INITIAL_EXEC
-   -ftls-model=initial-exec HWASAN_DYNAMIC_CFLAGS)
- append_list_if(MSVC /DEBUG HWASAN_DYNAMIC_LINK_FLAGS)
-@@ -132,7 +132,7 @@ foreach(arch ${HWASAN_SUPPORTED_ARCH})
-                                   LIBS clang_rt.hwasan-${arch} clang_rt.hwasan_cxx-${arch}
-                                   EXTRA hwasan.syms.extra)
-     set(VERSION_SCRIPT_FLAG
--         -Wl,--version-script,${CMAKE_CURRENT_BINARY_DIR}/clang_rt.hwasan-dynamic-${arch}.vers)
-+         -Wl,--version-script,${CMAKE_CURRENT_BINARY_DIR}/clang_rt.hwasan-dynamic-${arch}.vers -fuse-ld=gold)
-     set_property(SOURCE
-       ${CMAKE_CURRENT_BINARY_DIR}/dummy.cpp
-       APPEND PROPERTY
diff --git a/debian/qualify-clang.sh b/debian/qualify-clang.sh
index 7c9861a6..e6d2734a 100755
--- a/debian/qualify-clang.sh
+++ b/debian/qualify-clang.sh
@@ -1412,8 +1412,9 @@ echo "Testing all other sanitizers ..."
 echo "int main() { return 1; }" > foo.c
 # fails to run on i386 with the following error:
 #clang: error: unsupported option '-fsanitize=efficiency-working-set' for target 'i686-pc-linux-gnu'
-clang-$VERSION -fsanitize=efficiency-working-set -o foo foo.c || true
-./foo &> /dev/null || true
+# seems like esan was removed from clang: https://github.com/llvm/llvm-project/commit/885b790f89b6068ec4caad8eaa51aa8098327059
+#clang-$VERSION -fsanitize=efficiency-working-set -o foo foo.c || true
+#./foo &> /dev/null || true
 
 cat > "$TEMPDIR/test.c" <<EOF
 #include <stdlib.h>
diff --git a/debian/rules b/debian/rules
index c994960b..cadb0396 100755
--- a/debian/rules
+++ b/debian/rules
@@ -1,7 +1,9 @@
 #!/usr/bin/make -f
 
-# polly, openmp & lldb aren't enabled for every platform
-PROJECTS = clang;clang-tools-extra;libcxx;libcxxabi;compiler-rt;lld;debuginfo-tests
+# polly & lldb aren't enabled for every platform
+PROJECTS = clang;clang-tools-extra;lld;debuginfo-tests
+# openmp & libunwind aren't enabled for every platform
+RUNTIMES = compiler-rt;libcxx;libcxxabi
 
 TARGET_BUILD	:= build-llvm
 TARGET_BUILD_STAGE2    := $(TARGET_BUILD)/tools/clang/stage2-bins
@@ -40,17 +42,24 @@ CXXFLAGS_EXTRA =
 CFLAGS_EXTRA =
 CONFIGURE_EXTRA =
 CMAKE_EXTRA = -DPYTHON_EXECUTABLE=/usr/bin/python3
-CMAKE_LIBCXX_EXTRA =
+STAGE1_CMAKE_EXTRA =
+# prepend bootstrap prefix to CMAKE_EXTRA vars
+BOOTSTRAP_CMAKE_EXTRA = $(foreach extra,$(CMAKE_EXTRA), $(subst -D,-DBOOTSTRAP_,$(extra)))
 
-BASE_PATH	:= $(CURDIR)
-LIBCXX_EXCEPTIONS :=ON
+BASE_PATH := $(CURDIR)
+STAGE1_BIN_DIR := $(BASE_PATH)/$(TARGET_BUILD)/bin
+STAGE1_LIB_DIR := $(BASE_PATH)/$(TARGET_BUILD)/lib
+STAGE2_BIN_DIR := $(BASE_PATH)/$(TARGET_BUILD_STAGE2)/bin
+STAGE2_LIB_DIR := $(BASE_PATH)/$(TARGET_BUILD_STAGE2)/lib
 
+LIBCXX_EXCEPTIONS := ON
 ifneq (,$(filter $(DEB_HOST_ARCH),s390x))
 	LIBCXX_EXCEPTIONS :=OFF
 endif
 
 ifneq (,$(filter $(DEB_HOST_ARCH),i386 armel mips mipsel powerpc powerpcspe riscv64))
-CMAKE_EXTRA += -DLIBOMP_LIBFLAGS="-latomic" -DCMAKE_SHARED_LINKER_FLAGS="-latomic"
+CMAKE_EXTRA += -DCMAKE_SHARED_LINKER_FLAGS="-latomic"
+STAGE1_CMAKE_EXTRA += -DCMAKE_SHARED_LINKER_FLAGS="-latomic"
 endif
 
 ifneq (,$(filter $(DEB_HOST_ARCH),sparc sparc64))
@@ -83,6 +92,7 @@ ifneq ($(shell dpkg-vendor --derives-from Ubuntu && echo yes),yes)
 	Z3_FLAG = -DLLVM_ENABLE_Z3_SOLVER=ON
 endif
 endif
+CMAKE_EXTRA += $(Z3_FLAG)
 
 # Change the default CPU for s390x
 ZARCH=z196
@@ -101,23 +111,22 @@ ifneq (,$(findstring $(DEB_HOST_ARCH),armel))
   # 3.8 fails to build, disable the compiler_rt builtins
   # See http://lists.llvm.org/pipermail/llvm-dev/2016-May/099761.html
   CMAKE_EXTRA += -DCOMPILER_RT_BUILD_BUILTINS=OFF
-  # Check for ancient libstdc++ fails due to atomics usage
-  CMAKE_LIBCXX_EXTRA += -DLLVM_COMPILER_CHECKED=ON
+  STAGE1_CMAKE_EXTRA += -DCOMPILER_RT_BUILD_BUILTINS=OFF
   # Prevent clang from getting a > v4t default
   # See bug #868779
-  CMAKE_EXTRA += -DLLVM_HOST_TRIPLE=arm-linux-gnueabi
+  STAGE1_CMAKE_EXTRA += -DLLVM_HOST_TRIPLE=arm-linux-gnueabi
 endif
 
 
 ifneq (,$(findstring $(DEB_HOST_ARCH),armhf))
 # avoid an issue with openmp on armhf
-  CMAKE_EXTRA += -DLLVM_HOST_TRIPLE=armv7l-unknown-linux-gnueabihf
+  STAGE1_CMAKE_EXTRA += -DLLVM_HOST_TRIPLE=armv7l-unknown-linux-gnueabihf
 endif
 
 ifneq (,$(filter $(DEB_HOST_ARCH),mips64el))
 # avoid an issue with search path on mips64el
 # https://bugs.llvm.org/show_bug.cgi?id=41204
-  CMAKE_EXTRA += -DLLVM_HOST_TRIPLE=mips64el-linux-gnuabi64
+  STAGE1_CMAKE_EXTRA += -DLLVM_HOST_TRIPLE=mips64el-linux-gnuabi64
 endif
 
 
@@ -142,23 +151,11 @@ ifeq ($(LLVM_SPIRV_INSTALLED),yes)
 	LIBCLC_TARGETS_TO_BUILD := $(LIBCLC_TARGETS_TO_BUILD)";spirv-mesa3d-;spirv64-mesa3d-"
 endif
 
-# Disabled:
-#  Host compiler does not support '-fuse-ld=lld'
-# USE_LLD_ARCHS := amd64
-# ifneq (,$(filter $(DEB_HOST_ARCH),$(USE_LLD_ARCHS)))
-# 	CMAKE_EXTRA += -DLLVM_ENABLE_LLD=ON
-# endif
-
 BINUTILS_GOLD_ARCHS := amd64 arm64 armhf i386 ppc64 ppc64el x32 s390x hurd-i386 kfreebsd-amd64 kfreebsd-i386
 ifeq ($(shell dpkg --compare-versions $(shell dpkg-query -W -f '$${Version}' binutils) ge 2.23.1-1~exp3 ; echo $$?),0)
 ifneq (,$(filter $(DEB_HOST_ARCH),$(BINUTILS_GOLD_ARCHS)))
-# -fused-ld=gold enables the gold linker (but is not supported by all archs / distro)
-	LDFLAGS_EXTRA += -fuse-ld=gold
-#--no-keep-files-mapped --no-map-whole-files
-	CXXFLAGS_EXTRA += -fuse-ld=gold
-	CFLAGS_EXTRA += -fuse-ld=gold
-#-Wl,--no-keep-files-mapped -Wl,--no-map-whole-files
-	CMAKE_EXTRA += -DLLVM_BINUTILS_INCDIR=/usr/include/
+	STAGE1_CMAKE_EXTRA += -DLLVM_USE_LINKER=gold
+	STAGE1_CMAKE_EXTRA += -DLLVM_BINUTILS_INCDIR=/usr/include/
 endif
 endif
 
@@ -175,11 +172,12 @@ ifneq (,$(filter codecoverage,$(DEB_BUILD_OPTIONS)))
 endif
 
 # Enable for bootstrap
-LDFLAGS_EXTRA            += -fPIC -Wno-unused-command-line-argument -Wno-unknown-warning-option -Wl,--build-id
-CXXFLAGS_EXTRA           += -fPIC -Wno-unused-command-line-argument -Wno-unknown-warning-option
-BOOTSTRAP_CXXFLAGS_EXTRA  = $(CXXFLAGS_EXTRA) # Nothing for now. Keeping in case we need it
-CFLAGS_EXTRA             += -fPIC -Wno-unused-command-line-argument -Wno-unknown-warning-option
-BOOTSTRAP_CFLAGS_EXTRA    = $(CFLAGS_EXTRA) # Nothing for now. Keeping in case we need it
+CFLAGS_EXTRA             += -Wno-unused-command-line-argument
+CXXFLAGS_EXTRA           += -Wno-unused-command-line-argument
+LDFLAGS_EXTRA            += -Wno-unused-command-line-argument -Wl,--build-id
+BOOTSTRAP_CFLAGS_EXTRA    = $(CFLAGS_EXTRA)
+BOOTSTRAP_CXXFLAGS_EXTRA  = $(CXXFLAGS_EXTRA)
+BOOTSTRAP_LDFLAGS_EXTRA   =
 
 # Enable polly (or not)
 POLLY_ENABLE=yes
@@ -189,22 +187,28 @@ else
   PROJECTS+=;polly
 endif
 
-# Enable openmp (or not)
-OPENMP_ENABLE=yes
-ifneq (,$(filter $(DEB_HOST_ARCH), mips mipsel powerpc powerpcspe sparc64 s390x x32))
-  OPENMP_ENABLE=no
-else
-  PROJECTS+=;openmp
-endif
-
 # Enable libunwind (or not)
 LIBUNWIND_ENABLE=yes
 ifneq (,$(filter $(DEB_HOST_ARCH), s390x armel mipsel hurd-i386 powerpc sparc sparc64 x32))
   LIBUNWIND_ENABLE=no
 else
-  PROJECTS += ;libunwind
-  CMAKE_LIBCXX_EXTRA += -DLIBCXXABI_USE_LLVM_UNWINDER=ON \
-	-DLIBUNWIND_USE_COMPILER_RT=ON
+  RUNTIMES += ;libunwind
+# this is also added to stage2 via CLANG_BOOTSTRAP_PASSTHROUGH
+  STAGE1_CMAKE_EXTRA += -DLIBCXXABI_USE_LLVM_UNWINDER=ON
+endif
+
+# Enable openmp (or not)
+OPENMP_ENABLE=yes
+ifneq (,$(filter $(DEB_HOST_ARCH), mips mipsel powerpc powerpcspe sparc64 s390x x32))
+  OPENMP_ENABLE=no
+else
+  RUNTIMES+=;openmp
+# this is also added to stage2 via CLANG_BOOTSTRAP_PASSTHROUGH
+  STAGE1_CMAKE_EXTRA += -DLIBOMP_LIBFLAGS="-lm"
+ifeq ($(LIBUNWIND_ENABLE),yes)
+# this is also added to stage2 via CLANG_BOOTSTRAP_PASSTHROUGH
+  STAGE1_CMAKE_EXTRA += -DOPENMP_USE_LLVM_UNWINDER=ON
+endif
 endif
 
 RUN_TEST=yes
@@ -233,7 +237,8 @@ ifneq (,$(filter scan-build,$(DEB_BUILD_OPTIONS)))
 # no need to run tests in this case
 	RUN_TEST=no
 	CONFIGURE_EXTRA += --enable-assertions
-	CMAKE_EXTRA += -DLLVM_ENABLE_ASSERTIONS=ON
+# will also be applied to stage2 via CLANG_BOOTSTRAP_PASSTHROUGH
+	STAGE1_CMAKE_EXTRA += -DLLVM_ENABLE_ASSERTIONS=ON
 endif
 
 ifneq (,$(filter coverity,$(DEB_BUILD_OPTIONS)))
@@ -246,7 +251,8 @@ ifneq (,$(filter coverity,$(DEB_BUILD_OPTIONS)))
 	PRE_PROCESS_CONF=
 	COVERITY_ENABLE=1
 	CONFIGURE_EXTRA += --enable-assertions
-	CMAKE_EXTRA += -DLLVM_ENABLE_ASSERTIONS=ON
+# will also be applied to stage2 via CLANG_BOOTSTRAP_PASSTHROUGH
+	STAGE1_CMAKE_EXTRA += -DLLVM_ENABLE_ASSERTIONS=ON
 # no need to run tests in this case
 	RUN_TEST=no
 else
@@ -270,7 +276,7 @@ LLD_ENABLE=yes
 
 ifneq (,$(filter $(DEB_HOST_ARCH_OS),linux))
 # only for linux
-	CMAKE_EXTRA += -DLLVM_USE_PERF=yes -DLLVM_ENABLE_LIBPFM=ON
+	CMAKE_EXTRA += -DLLVM_USE_PERF=ON -DLLVM_ENABLE_LIBPFM=ON
 endif
 
 # Only enable it for archs supporting gold
@@ -321,12 +327,15 @@ endif
 
 GENERATOR=Ninja
 
+# enables cmake build targets like stage2-[target_name]
+ENABLED_STAGE2_CMAKE_BUILD_TARGETS = check-all;check-llvm;check-clang;check-clang-tools;check-lld;check-libcxx;check-libcxxabi;check-sanitizer;llvm-config;test-suite
+
 %:
 	dh $@ $(DH_OPTIONS)
 
 # For some reasons, some spaces are added, removing them
 PROJECTS_LIST := $(shell echo "$(PROJECTS)"|sed -e "s| ||g")
-#RUNTIMES_LIST := $(shell echo "$(RUNTIMES)"|sed -e "s| ||g")
+RUNTIMES_LIST := $(shell echo "$(RUNTIMES)"|sed -e "s| ||g")
 
 preconfigure:
 
@@ -343,7 +352,7 @@ preconfigure:
 	@echo "DISTRO=$(DISTRO)"
 	@echo "GCC_VERSION=$(GCC_VERSION)"
 	@echo "PROJECTS=$(PROJECTS_LIST)"
-#	@echo "RUNTIMES=$(RUNTIMES_LIST)"
+	@echo "RUNTIMES=$(RUNTIMES_LIST)"
 	@echo "LLVM_VERSION=$(LLVM_VERSION)"
 	@echo "LLVM_VERSION_FULL=$(LLVM_VERSION_FULL)"
 	@echo "LLVM_VERSION_SNAPSHOT=$(LLVM_VERSION_SNAPSHOT)"
@@ -414,6 +423,14 @@ override_dh_auto_configure: preconfigure
 			--xml-option append_arg:"replace/llvm::AlignOf<NextTy>::Alignment/(llvm::AlignOf<NextTy>::Alignment)"; \
 	fi)
 
+# Fails with No target "unwind_static"
+#    -DLIBCXXABI_ENABLE_STATIC_UNWINDER=ON \
+#    -DLIBCXXABI_STATICALLY_LINK_UNWINDER_IN_SHARED_LIBRARY=OFF \
+#    -DLIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC_LIBRARY=ON \
+#-    to libc++ when libunwind is built
+#-    Matches what is done on brew:
+#-    https://bit.ly/3kDNpC9
+
 	echo "Running tests: $(RUN_TEST)"
 	echo "Using cmake: $(CMAKE_BIN)"; \
 	CFLAGS="$(CFLAGS_EXTRA)" \
@@ -421,49 +438,92 @@ override_dh_auto_configure: preconfigure
 	LDFLAGS="$(LDFLAGS_EXTRA)" \
 	LD_LIBRARY_PATH=$$LD_LIBRARY_PATH $(PRE_PROCESS_CONF) $(CMAKE_BIN) -S llvm/ -B $(TARGET_BUILD) \
 	-G $(GENERATOR) \
-	-DLLVM_ENABLE_PROJECTS="$(PROJECTS_LIST)" \
-	-DCMAKE_SUPPRESS_REGENERATION=ON \
 	-DCMAKE_INSTALL_PREFIX=/usr/lib/llvm-$(LLVM_VERSION) \
-	-DCMAKE_VERBOSE_MAKEFILE=ON \
-	-DCMAKE_BUILD_TYPE=RelWithDebInfo \
-	-DCMAKE_CXX_FLAGS_RELWITHDEBINFO="$(opt_flags)" \
-	-DCMAKE_POSITION_INDEPENDENT_CODE=ON \
-	-DLLVM_LINK_LLVM_DYLIB=ON \
-	-DLLVM_INSTALL_UTILS=ON \
-	-DLLVM_VERSION_SUFFIX= \
-	-DLLVM_ENABLE_SPHINX=ON \
-	-DSPHINX_WARNINGS_AS_ERRORS=OFF \
-	-DLLVM_ENABLE_RTTI=ON \
-	-DLLVM_ENABLE_FFI=ON \
-	-DLLVM_ENABLE_DUMP=ON \
-	-DLIBCLANG_LIBRARY_VERSION=$(SONAME_EXT) \
-	-DCLANG_LINK_CLANG_DYLIB=ON \
+	-DCMAKE_SUPPRESS_REGENERATION=ON \
+	-DCMAKE_BUILD_TYPE=Release \
+	-DPACKAGE_VENDOR=$(VENDOR) \
 	-DENABLE_LINKER_BUILD_ID=ON \
-	-DCOMPILER_RT_USE_LIBCXX=NO \
-	-DLIBUNWIND_USE_COMPILER_RT=ON \
-	$(Z3_FLAG) \
-	$(CMAKE_EXTRA) \
-	-DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD="AVR" \
+	-DLLVM_TARGETS_TO_BUILD=Native \
+	-DLLVM_ENABLE_PROJECTS="$(PROJECTS_LIST)" \
+	-DLLVM_ENABLE_RUNTIMES="$(RUNTIMES_LIST)" \
+	-DLLVM_ENABLE_PIC=ON \
+	-DLLVM_ENABLE_RTTI=ON \
+	-DLVVM_ENABLE_ZLIB=OFF \
+	-DLLVM_BUILD_DOCS=OFF \
+	-DLLVM_INCLUDE_GO_TESTS=OFF \
 	-DLLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN=ON \
-	-DCLANG_VENDOR=$(VENDOR) \
-	-DCLANG_ENABLE_BOOTSTRAP=ON \
+	-DCLANG_PLUGIN_SUPPORT=OFF \
 	-DCLANG_BUILD_EXAMPLES=OFF \
-	-DLLVM_POLLY_LINK_INTO_TOOLS=ON \
-	-DBOOTSTRAP_CMAKE_CXX_FLAGS='$(BOOTSTRAP_CXXFLAGS_EXTRA)' \
-	-DBOOTSTRAP_CMAKE_C_FLAGS='$(BOOTSTRAP_CFLAGS_EXTRA)' \
-	-DCLANG_BOOTSTRAP_PASSTHROUGH="CMAKE_INSTALL_PREFIX;CMAKE_VERBOSE_MAKEFILE;CMAKE_BUILD_TYPE;CMAKE_CXX_FLAGS_RELWITHDEBINFO;LLVM_LINK_LLVM_DYLIB;LLVM_INSTALL_UTILS;LLVM_VERSION_SUFFIX;LLVM_ENABLE_SPHINX;SPHINX_WARNINGS_AS_ERRORS;LLVM_BUILD_LLVM_DYLIB;LLVM_ENABLE_RTTI;LLVM_ENABLE_FFI;LIBCLANG_LIBRARY_VERSION;ENABLE_LINKER_BUILD_ID;POLLY_BUNDLED_JSONCPP;LLVM_EXPERIMENTAL_TARGETS_TO_BUILD;LLVM_USE_PERF;LLVM_ENABLE_ASSERTIONS;LLVM_BINUTILS_INCDIR;LLVM_HOST_TRIPLE;LLVM_COMPILER_CHECKED;COMPILER_RT_BUILD_BUILTINS;LIBOMP_LIBFLAGS;CMAKE_SHARED_LINKER_FLAGS;PYTHON_EXECUTABLE;LLVM_ENABLE_Z3_SOLVER;LLVM_POLLY_LINK_INTO_TOOLS;CLANG_VENDOR;LIBUNWIND_USE_COMPILER_RT"; \
+	-DCLANG_DEFAULT_LINKER=ld \
+	-DCLANG_DEFAULT_CXX_STDLIB=libstdc++ \
+	-DCLANG_DEFAULT_RTLIB=libgcc \
+	-DCOMPILER_RT_BUILD_XRAY=OFF \
+	-DCOMPILER_RT_INCLUDE_TESTS=OFF \
+	-DCOMPILER_RT_USE_LIBCXX=NO \
+	-DCOMPILER_RT_USE_BUILTINS_LIBRARY=ON \
+	-DLIBUNWIND_ENABLE_SHARED=ON \
+	-DLIBUNWIND_USE_COMPILER_RT=ON \
+	-DLIBUNWIND_INSTALL_LIBRARY=OFF \
+	-DLIBCXXABI_ENABLE_SHARED=ON \
+	-DLIBCXXABI_USE_COMPILER_RT=ON \
+	-DLIBCXXABI_INSTALL_LIBRARY=OFF \
+	-DLIBCXX_ENABLE_SHARED=ON \
+	-DLIBCXX_USE_COMPILER_RT=ON \
+	-DLIBCXX_ENABLE_STATIC_ABI_LIBRARY=ON \
+	-DLIBCXX_STATICALLY_LINK_ABI_IN_STATIC_LIBRARY=ON \
+	-DLIBCXX_STATICALLY_LINK_ABI_IN_SHARED_LIBRARY=OFF \
+	-DLIBCXX_INSTALL_LIBRARY=OFF \
+	-DOPENMP_ENABLE_LIBOMP_PROFILING=OFF \
+	-DOPENMP_ENABLE_LIBOMPTARGET_PROFILING=OFF \
+	-DLIBOMP_ENABLE_RTTI=OFF \
+	-DLIBOMP_OMPT_SUPPORT=OFF \
+	$(STAGE1_CMAKE_EXTRA) \
+	-DBUILTINS_CMAKE_ARGS="-DCMAKE_SYSTEM_NAME=Linux;-DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF" \
+	-DRUNTIMES_CMAKE_ARGS="-DCMAKE_SYSTEM_NAME=Linux;-DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF" \
+	-DCLANG_ENABLE_BOOTSTRAP=ON \
+	-DCLANG_BOOTSTRAP_TARGETS="$(ENABLED_STAGE2_CMAKE_BUILD_TARGETS)" \
+	-DBOOTSTRAP_CMAKE_BUILD_TYPE=RelWithDebInfo \
+	-DBOOTSTRAP_CMAKE_C_FLAGS_RELWITHDEBINFO="$(opt_flags)" \
+	-DBOOTSTRAP_CMAKE_CXX_FLAGS_RELWITHDEBINFO="$(opt_flags)" \
+	-DBOOTSTRAP_CMAKE_CXX_FLAGS="$(BOOTSTRAP_CXXFLAGS_EXTRA)" \
+	-DBOOTSTRAP_CMAKE_C_FLAGS="$(BOOTSTRAP_CFLAGS_EXTRA)" \
+	-DBOOTSTRAP_CMAKE_SHARED_LINKER_FLAGS="$(BOOTSTRAP_LDFLAGS_EXTRA)" \
+	-DBOOTSTRAP_CMAKE_MODULE_LINKER_FLAGS="$(BOOTSTRAP_LDFLAGS_EXTRA)" \
+	-DBOOTSTRAP_CMAKE_EXE_LINKER_FLAGS="$(BOOTSTRAP_LDFLAGS_EXTRA)" \
+	-DBOOTSTRAP_LLVM_ENABLE_FFI=ON \
+	-DBOOTSTRAP_LLVM_ENABLE_DUMP=ON \
+	-DBOOTSTRAP_LLVM_ENABLE_LIBPFM=ON \
+	-DBOOTSTRAP_LLVM_ENABLE_SPHINX=ON \
+	-DBOOTSTRAP_SPHINX_WARNINGS_AS_ERRORS=OFF \
+	-DBOOTSTRAP_LLVM_USE_RELATIVE_PATHS_IN_FILES=ON \
+	-DBOOTSTRAP_LLVM_INSTALL_UTILS=ON \
+	-DBOOTSTRAP_LLVM_VERSION_SUFFIX= \
+	-DBOOTSTRAP_LLVM_POLLY_LINK_INTO_TOOLS=ON \
+	-DBOOTSTRAP_LLVM_EXPERIMENTAL_TARGETS_TO_BUILD="AVR" \
+	-DBOOTSTRAP_LLVM_LINK_LLVM_DYLIB=ON \
+	-DBOOTSTRAP_CLANG_LINK_CLANG_DYLIB=ON \
+	-DBOOTSTRAP_LIBCLANG_LIBRARY_VERSION=$(SONAME_EXT) \
+	-DBOOTSTRAP_LIBCXXABI_ENABLE_EXCEPTIONS=$(LIBCXX_EXCEPTIONS) \
+	-DBOOTSTRAP_LIBCXX_ENABLE_EXCEPTIONS=$(LIBCXX_EXCEPTIONS) \
+	-DBOOTSTRAP_LIBCXX_INSTALL_EXPERIMENTAL_LIBRARY=ON \
+	$(BOOTSTRAP_CMAKE_EXTRA) \
+	-DBOOTSTRAP_BUILTINS_CMAKE_ARGS="-DCMAKE_SYSTEM_NAME=Linux;-DCMAKE_BUILD_TYPE=RelWithDebInfo;-DCMAKE_C_FLAGS_RELWITHDEBINFO=$(opt_flags);-DCMAKE_CXX_FLAGS_RELWITHDEBINFO=$(opt_flags);-DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF" \
+	-DBOOTSTRAP_RUNTIMES_CMAKE_ARGS="-DCMAKE_CXX_FLAGS=$(BOOTSTRAP_CXXFLAGS_EXTRA);-DCMAKE_EXE_LINKER_FLAGS=$(BOOTSTRAP_LDFLAGS_EXTRA) -L$(STAGE1_LIB_DIR);-DCMAKE_SHARED_LINKER_FLAGS=$(BOOTSTRAP_LDFLAGS_EXTRA) -L$(STAGE1_LIB_DIR);-DCMAKE_MODULE_LINKER_FLAGS=$(BOOTSTRAP_LDFLAGS_EXTRA) -L$(STAGE1_LIB_DIR);-DCMAKE_SYSTEM_NAME=Linux;-DCMAKE_BUILD_TYPE=RelWithDebInfo;-DCMAKE_C_FLAGS_RELWITHDEBINFO=$(opt_flags);-DCMAKE_CXX_FLAGS_RELWITHDEBINFO=$(opt_flags);-DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF" \
+	-DCLANG_BOOTSTRAP_PASSTHROUGH="CMAKE_INSTALL_PREFIX;CMAKE_SUPPRESS_REGENERATION;ENABLE_LINKER_BUILD_ID;LLVM_HOST_TRIPLE;LLVM_ENABLE_PIC;LLVM_ENABLE_RTTI;LLVM_ENABLE_ASSERTIONS;LLVM_INCLUDE_GO_TESTS;LLVM_BINUTILS_INCDIR;LLVM_USE_LINKER;CLANG_DEFAULT_LINKER;CLANG_DEFAULT_CXX_STDLIB;CLANG_DEFAULT_RTLIB;COMPILER_RT_USE_LIBCXX;COMPILER_RT_USE_BUILTINS_LIBRARY;COMPILER_RT_INCLUDE_TESTS;LIBUNWIND_ENABLE_SHARED;LIBCXXABI_ENABLE_SHARED;LIBCXXABI_USE_COMPILER_RT;LIBCXXABI_USE_LLVM_UNWINDER;LIBCXX_USE_COMPILER_RT;LIBCXX_ENABLE_SHARED;LIBCXX_ENABLE_STATIC_ABI_LIBRARY;LIBCXX_STATICALLY_LINK_ABI_IN_STATIC_LIBRARY;LIBCXX_STATICALLY_LINK_ABI_IN_SHARED_LIBRARY;OPENMP_USE_LLVM_UNWINDER;LIBOMP_LIBFLAGS;LIBOMP_ENABLE_RTTI;PYTHON_EXECUTABLE"
 	FOUND_VERSION=`grep LLVM_VERSION_STRING build-llvm/include/llvm/Config/llvm-config.h|cut -d\" -f2`; \
 	if ! echo "$(LLVM_VERSION_FULL)"|grep "$$FOUND_VERSION"; then \
 		echo "mistmatch of version. Found: $$FOUND_VERSION / Expected: $(LLVM_VERSION_FULL)"; \
 		exit 1; \
 	fi
 
-
 # ninja
 VERBOSE=-v
 
 debian-full-build:
-	$(PRE_PROCESS) ninja $(NJOBS) -C $(TARGET_BUILD) $(VERBOSE) stage2
+	echo "Using cmake: $(CMAKE_BIN)"
+#	linker hack so stage2 can link against stage1 libs at runtime
+	LD_LIBRARY_PATH=$(STAGE1_LIB_DIR):$$LD_LIBRARY_PATH \
+	VERBOSE=1 $(PRE_PROCESS) $(CMAKE_BIN) --build $(TARGET_BUILD) $(NJOBS) --target stage2
 
 # Check the stage 2 build worked
 	if ! readelf --string-dump .comment  $(TARGET_BUILD_STAGE2)/bin/clang 2>&1|grep -q "clang version"; then \
@@ -474,8 +534,6 @@ debian-full-build:
 		echo "libclang-$(LLVM_VERSION).so.1 depends on libclang-cpp. Should not be the case"; \
 		exit 2; \
 	fi
-#	$(PRE_PROCESS) make $(NJOBS) -C $(TARGET_BUILD) $(VERBOSE) CFLAGS="$(CFLAGS_EXTRA)" CXXFLAGS="$(CXXFLAGS_EXTRA)"  LDFLAGS="$(LDFLAGS_EXTRA)" REQUIRES_RTTI=1 DEBUGMAKE=1 runtimes
-
 	touch $@
 
 debian-libfuzzer-build:
@@ -484,104 +542,33 @@ ifeq (${LIBFUZZER_ENABLE},yes)
 	CFLAGS=`dpkg-buildflags --get CFLAGS`; \
 	CFLAGS="$$CFLAGS `dpkg-buildflags --get CPPFLAGS`"; \
 	echo $$CFLAGS; \
-	$(BASE_PATH)/$(TARGET_BUILD_STAGE2)/bin/clang++ -c $$CFLAGS -std=c++11 $(BASE_PATH)/compiler-rt/lib/fuzzer/*.cpp -IFuzzer; \
+	$(STAGE2_BIN_DIR)/clang++ -c $$CFLAGS -std=c++11 $(BASE_PATH)/compiler-rt/lib/fuzzer/*.cpp -IFuzzer; \
 	ar ruv libFuzzer.a Fuzzer*.o
 endif
 	touch $@
 
-# The various options to build libc++ and libc++abi
-
-LIBCXX_CMAKE_OPTIONS := \
-	-DCMAKE_INSTALL_PREFIX=/usr/lib/llvm-$(LLVM_VERSION) \
-	-DLLVM_CONFIG_PATH=$(CURDIR)/$(TARGET_BUILD_STAGE2)/bin/llvm-config \
-	-DCMAKE_BUILD_TYPE=RelWithDebInfo \
-	-DCMAKE_CXX_COMPILER=$(CURDIR)/$(TARGET_BUILD_STAGE2)/bin/clang++ \
-	-DCMAKE_C_COMPILER=$(CURDIR)/$(TARGET_BUILD_STAGE2)/bin/clang \
-	-DCMAKE_CXX_FLAGS="$(LIBCXXFLAGS)" \
-	-DCMAKE_EXE_LINKER_FLAGS="" \
-	-DCMAKE_SHARED_LINKER_FLAGS="" \
-	-DCMAKE_MODULE_LINKER_FLAGS="" \
-	-DCMAKE_AR=$(CURDIR)/$(TARGET_BUILD_STAGE2)/bin/llvm-ar \
-	-DCMAKE_RANLIB=$(CURDIR)/$(TARGET_BUILD_STAGE2)/bin/llvm-ranlib \
-	-DLLVM_EXTERNAL_LIT=$(BASE_PATH)/llvm/utils/lit/lit.py \
-	-DLLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN=ON \
-	$(CMAKE_EXTRA)
-
-debian-libcxxabi-build:
-# Builds libcxxabi
-	echo "Using cmake: $(CMAKE_BIN)"; \
-	cd libcxxabi && \
-	CXXFLAGS="$(CXXFLAGS_EXTRA)" LDFLAGS="$(LDFLAGS_EXTRA)" \
-	$(PRE_PROCESS_CONF) $(CMAKE_BIN) \
-	-S . -B build \
-	-G $(GENERATOR) \
-	$(LIBCXX_CMAKE_OPTIONS) \
-	-DLIBCXXABI_LIBCXX_PATH=$(BASE_PATH)/libcxx \
-	-DLIBCXXABI_LIBCXX_LIBRARY_PATH=$(BASE_PATH)/libcxx/build/lib \
-	-DLIBCXXABI_LIBCXX_INCLUDES=$(BASE_PATH)/libcxx/include \
-	-DLIBCXXABI_ENABLE_EXCEPTIONS=$(LIBCXX_EXCEPTIONS) \
-	-DLIBCXXABI_USE_COMPILER_RT=ON \
-	-DLLVM_ENABLE_RTTI=ON \
-	$(CMAKE_LIBCXX_EXTRA) &&  \
-	$(PRE_PROCESS_CONF) ninja -C build/ $(VERBOSE)
-	touch $@
-
-# Fails with    $<TARGET_LINKER_FILE:unwind_static>
-#  No target "unwind_static"
-# on 12. Will test with 13
-# -DLIBCXXABI_ENABLE_STATIC_UNWINDER=ON \
-#    -DLIBCXXABI_STATICALLY_LINK_UNWINDER_IN_SHARED_LIBRARY=OFF \
-#    -DLIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC_LIBRARY=ON \
-N
-#-    to libc++ when libunwind is built
-#-    Matches what is done on brew:
-#-    https://bit.ly/3kDNpC9
-
-debian-libcxx-build:
-# Builds libcxx
-	echo "Using cmake: $(CMAKE_BIN)"; \
-	cd libcxx && \
-	$(PRE_PROCESS_CONF) $(CMAKE_BIN) \
-	CXXFLAGS="$(CXXFLAGS_EXTRA)" LDFLAGS="$(LDFLAGS_EXTRA)" \
-	-S . -B build \
-	-G $(GENERATOR) \
-	$(LIBCXX_CMAKE_OPTIONS) \
-	-DLIBCXX_CXX_ABI=libcxxabi \
-	-DLIBCXX_CXX_ABI_INCLUDE_PATHS=$(BASE_PATH)/libcxxabi/include \
-	-DLIBCXX_CXX_ABI_LIBRARY_PATH=$(BASE_PATH)/libcxxabi/build/lib \
-	-DLIBCXX_ENABLE_EXCEPTIONS=$(LIBCXX_EXCEPTIONS) \
-	-DLIBCXX_INSTALL_EXPERIMENTAL_LIBRARY=ON \
-	-DLIBCXX_USE_COMPILER_RT=ON \
-	-DLIBCXX_ENABLE_STATIC_ABI_LIBRARY=ON \
-	-DLIBCXX_STATICALLY_LINK_ABI_IN_STATIC_LIBRARY=ON \
-	-DLIBCXX_STATICALLY_LINK_ABI_IN_SHARED_LIBRARY=OFF \
-	$(CMAKE_LIBCXX_EXTRA) && \
-	$(PRE_PROCESS_CONF) ninja -C build/ $(VERBOSE)
-	touch $@
-
-
 debian-libclc-build:
 # Builds libclc
-
 	mkdir -p libclc/build
-
-	CMAKE_BIN=cmake; \
-	if test -f /tmp/cmake/bin/cmake; then \
-		CMAKE_BIN=/tmp/cmake/bin/cmake; \
-	fi; \
-	echo "Using cmake: $$CMAKE_BIN"; \
+	echo "Using cmake: $(CMAKE_BIN)"
 	cd libclc/build && \
-	$$CMAKE_BIN ../ \
+	$(CMAKE_BIN) ../ \
 	-G $(GENERATOR) \
+	-DCMAKE_C_COMPILER=$(STAGE2_BIN_DIR)/clang \
+	-DCMAKE_CXX_COMPILER=$(STAGE2_BIN_DIR)/clang++ \
+	-DCMAKE_CXX_FLAGS="$(BOOTSTRAP_CXXFLAGS_EXTRA)" \
+	-DCMAKE_SHARED_LINKER_FLAGS="$(BOOTSTRAP_LDFLAGS_EXTRA) -L$(STAGE2_LIB_DIR)" \
+	-DCMAKE_MODULE_LINKER_FLAGS="$(BOOTSTRAP_LDFLAGS_EXTRA) -L$(STAGE2_LIB_DIR)" \
+	-DCMAKE_EXE_LINKER_FLAGS="$(BOOTSTRAP_LDFLAGS_EXTRA) -L$(STAGE2_LIB_DIR)" \
 	-DCMAKE_INSTALL_PREFIX=/usr \
 	-DCMAKE_INSTALL_DATADIR=lib \
 	-DCMAKE_INSTALL_INCLUDEDIR=include \
-	-DLLVM_CONFIG=$(CURDIR)/$(TARGET_BUILD_STAGE2)/bin/llvm-config \
+	-DLLVM_CONFIG=$(STAGE2_BIN_DIR)/llvm-config \
 	-DLIBCLC_TARGETS_TO_BUILD=$(LIBCLC_TARGETS_TO_BUILD); \
-	ninja $(VERBOSE)
+	ninja $(NJOBS) $(VERBOSE)
 	touch $@
 
-override_dh_auto_build: debian-full-build debian-libfuzzer-build debian-libcxxabi-build debian-libcxx-build debian-libclc-build
+override_dh_auto_build: debian-full-build debian-libfuzzer-build debian-libclc-build
 
 override_dh_prep: build_doc
 	dh_prep
@@ -655,26 +642,21 @@ override_dh_auto_install:
 
 	# Only run on executable, not script
 	chrpath -d `find $(DEB_INST)/usr/lib/llvm-$(LLVM_VERSION)/bin/ -type f -executable -exec file -i '{}' \; | grep 'x-executable; charset=binary'|cut -d: -f1`
-	chrpath -d libcxxabi/build/lib/libc++abi.so.1.0
-	chrpath -d libcxx/build/lib/libc++.so.1.0
 
 	: # libclang
-	cd debian/tmp/usr/lib/llvm-$(LLVM_VERSION)/lib/ && rm -f libclang.so.$(SONAME_EXT) libclang-$(LLVM_VERSION).so; \
+	cd debian/tmp/usr/lib/llvm-$(LLVM_VERSION)/lib/ && rm -f libclang.so.$(SONAME_EXT); \
 	ln -s libclang-$(LLVM_VERSION).so.$(SONAME_EXT) libclang.so.$(SONAME_EXT)
 
-	: # libomp
-	cd debian/tmp/usr/lib/llvm-$(LLVM_VERSION)/lib && rm -f libomp.so; \
-	ln -s libomp.so.$(SONAME_OPENMP) libomp.so
-
 	if test "$(LIBUNWIND_ENABLE)" = yes; then \
 		mkdir -p debian/tmp/usr/include/libunwind; \
 		cp -R libunwind/include/* debian/tmp/usr/include/libunwind/; \
 	fi
 
+	: # libomp
 	if test "$(OPENMP_ENABLE)" = yes; then \
-		mkdir -p debian/tmp/usr/lib/llvm-$(LLVM_VERSION)/include/openmp; \
-		cp -f openmp/runtime/exports/common*/include/* debian/tmp/usr/lib/llvm-$(LLVM_VERSION)/include/openmp; \
-		cd debian/tmp/usr/lib/llvm-$(LLVM_VERSION)/lib && cp libomp.so.$(SONAME_OPENMP) libomp-$(LLVM_VERSION).so.$(SONAME_OPENMP); \
+		cd debian/tmp/usr/lib/llvm-$(LLVM_VERSION)/lib; \
+		ln -s libomp.so.$(SONAME_OPENMP) libomp.so; \
+		cp libomp.so.$(SONAME_OPENMP) libomp-$(LLVM_VERSION).so.$(SONAME_OPENMP); \
 	fi
 
 # Remove artifact (where compiler-rt is built)
@@ -714,8 +696,6 @@ endif
 	rm -rf $(DEB_INST)/usr/lib/llvm-$(LLVM_VERSION)/build/utils/lit/lit/__pycache__/ \
 	$(DEB_INST)/usr/lib/llvm-$(LLVM_VERSION)/build/utils/lit/lit/*/__pycache__/
 
-	DESTDIR=$(DEB_INST) ninja $(VERBOSE) -C libcxxabi/build install
-	DESTDIR=$(DEB_INST) ninja $(VERBOSE) -C libcxx/build install
 	DESTDIR=$(DEB_INST) ninja $(VERBOSE) -C libclc/build install
 
 # Rename binaries
@@ -769,8 +749,8 @@ endif
 # Manage the polly files. Sometimes, we build them. Sometimes not.
 	if test "$(POLLY_ENABLE)" = yes; then \
 		mkdir -p $(CURDIR)/debian/libclang-$(LLVM_VERSION)-dev/usr/lib/llvm-$(LLVM_VERSION)/lib/ $(CURDIR)/debian/libclang-common-$(LLVM_VERSION)-dev/usr/lib/llvm-$(LLVM_VERSION)/include/polly/; \
-		mv -f $(DEB_INST)/usr/lib/llvm-$(LLVM_VERSION)/lib/libpolly* \
-		$(CURDIR)/debian/libclang-$(LLVM_VERSION)-dev/usr/lib/llvm-$(LLVM_VERSION)/lib/; \
+		mv -f $(DEB_INST)/usr/lib/llvm-$(LLVM_VERSION)/lib/libPolly* \
+		$(CURDIR)/debian/libclang-common-$(LLVM_VERSION)-dev/usr/lib/llvm-$(LLVM_VERSION)/lib/; \
 		rm -rf $(CURDIR)/debian/libclang-common-$(LLVM_VERSION)-dev/usr/lib/llvm-$(LLVM_VERSION)/include/polly; \
 		mv -f $(DEB_INST)/usr/lib/llvm-$(LLVM_VERSION)/include/polly/ \
 		$(CURDIR)/debian/libclang-common-$(LLVM_VERSION)-dev/usr/lib/llvm-$(LLVM_VERSION)/include/; \
@@ -911,10 +891,10 @@ endif
 	ninja $(VERBOSE) -C $(TARGET_BUILD_STAGE2) check-sanitizer || true
 
 # Libcxx
-	ninja $(VERBOSE) -C libcxx/build check-libcxx || true
+	ninja $(VERBOSE) -C $(TARGET_BUILD_STAGE2) check-libcxx || true
 
 # Libcxxabi
-	ninja $(VERBOSE) -C libcxxabi/build check-libcxxabi || true
+	ninja $(VERBOSE) -C $(TARGET_BUILD_STAGE2) check-libcxxabi || true
 
 # Libclc
 	ninja $(VERBOSE) -C libclc/build test || true