diff --git a/zorg/buildbot/builders/sanitizers/buildbot_functions.sh b/zorg/buildbot/builders/sanitizers/buildbot_functions.sh
index 6c050986..76209797 100755
--- a/zorg/buildbot/builders/sanitizers/buildbot_functions.sh
+++ b/zorg/buildbot/builders/sanitizers/buildbot_functions.sh
@@ -1,474 +1,474 @@
 #!/usr/bin/env bash
 
 function include_config() {
   local P=.
   while true ; do
     local F=${P}/sanitizer_buildbot_config
     if [[ -f ${F} ]] ; then
       . ${F}
       break
     fi
     [[ "${P}" -ef '/' ]] && break
     P="${P}/.."
   done
 }
 
 include_config
 
 echo @@@BUILD_STEP Info@@@
 (
   set +e
   env
   echo
   uptime
   echo
   ulimit -n 1000000
   ulimit -a
   echo
   df -h
   echo
   ccache -ps
   exit 0
 )
 echo @@@BUILD_STEP Prepare@@@
 
 BUILDBOT_CLOBBER="${BUILDBOT_CLOBBER:-}"
 BUILDBOT_REVISION="${BUILDBOT_REVISION:-origin/main}"
 
 export LIT_OPTS="--time-tests"
 
 function rm_dirs {
   while ! rm -rf $@ ; do sleep 1; done
 }
 
 function cleanup() {
   [[ -v BUILDBOT_BUILDERNAME ]] || return 0
   echo @@@BUILD_STEP cleanup@@@
   rm_dirs llvm_build2_* llvm_build_* libcxx_build_* compiler_rt_build* symbolizer_build* $@
   if ccache -s >/dev/null ; then
     rm_dirs llvm_build64 clang_build
   fi
   ls
 }
 
 function clobber {
   if [[ "$BUILDBOT_CLOBBER" != "" ]]; then
     echo @@@BUILD_STEP clobber@@@
     if [[ ! -v BUILDBOT_BUILDERNAME ]]; then
       echo "Clobbering is supported only on buildbot only!"
       exit 1
     fi
     rm_dirs *
   else
     BUILDBOT_BUILDERNAME=1 cleanup $@
   fi
 }
 
 BUILDBOT_MONO_REPO_PATH=${BUILDBOT_MONO_REPO_PATH:-}
 
 function buildbot_update {
   echo @@@BUILD_STEP update $BUILDBOT_REVISION@@@
   if [[ -d "$BUILDBOT_MONO_REPO_PATH" ]]; then
     LLVM=$BUILDBOT_MONO_REPO_PATH/llvm
   else
     (
       local DEPTH=100
       [[ -d llvm-project ]] || (
         mkdir -p llvm-project
         cd llvm-project
         git init
         git remote add origin https://github.com/llvm/llvm-project.git
         git config --local advice.detachedHead false
       )
       cd llvm-project
       git fetch origin
       git clean -fd
       local REV=${BUILDBOT_REVISION}
       git checkout -f ${BUILDBOT_REVISION}
       git status
       git rev-list --pretty --max-count=1 HEAD
     ) || { build_exception ; exit 1 ; }
     LLVM=$ROOT/llvm-project/llvm
   fi
 }
 
 function common_stage1_variables {
   STAGE1_DIR=llvm_build0
   stage1_clang_path=$ROOT/${STAGE1_DIR}/bin
   llvm_symbolizer_path=${stage1_clang_path}/llvm-symbolizer
   export LLVM_SYMBOLIZER_PATH="${llvm_symbolizer_path}"
   STAGE1_AS_COMPILER="-DCMAKE_C_COMPILER=${stage1_clang_path}/clang -DCMAKE_CXX_COMPILER=${stage1_clang_path}/clang++"
 }
 
 function build_stage1_clang_impl {
   mkdir -p ${STAGE1_DIR}
   local cmake_stage1_options="${CMAKE_COMMON_OPTIONS} -DLLVM_ENABLE_PROJECTS='clang;compiler-rt;lld'"
   if clang -v ; then
     cmake_stage1_options+=" -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++"
   fi
   if ccache -s ; then
     cmake_stage1_options+=" -DLLVM_CCACHE_BUILD=ON"
   fi
   (cd ${STAGE1_DIR} && cmake ${cmake_stage1_options} $LLVM && ninja)
 }
 
 function build_stage1_clang {
   echo @@@BUILD_STEP stage1 build all@@@
   common_stage1_variables
   build_stage1_clang_impl
 }
 
 function download_clang_from_chromium {
   common_stage1_variables
 
   curl -s https://raw.githubusercontent.com/chromium/chromium/main/tools/clang/scripts/update.py \
     | python3 - --output-dir=${STAGE1_DIR}
 
   echo @@@BUILD_STEP using pre-built stage1 clang at $(cat ${STAGE1_DIR}/cr_build_revision)@@@
 }
 
 function build_clang_at_release_tag {
   local HOST_CLANG_REVISION=llvmorg-$(curl https://api.github.com/repos/llvm/llvm-project/releases/latest -s | jq .name -r | cut -f2 -d' ')
   common_stage1_variables
 
   if  [ -r ${STAGE1_DIR}/host_clang_revision ] && \
       [ "$(cat ${STAGE1_DIR}/host_clang_revision)" == $HOST_CLANG_REVISION ]
   then
     echo @@@BUILD_STEP using pre-built stage1 clang at r$HOST_CLANG_REVISION@@@
   else
     BUILDBOT_MONO_REPO_PATH= BUILDBOT_REVISION=$HOST_CLANG_REVISION buildbot_update
 
     rm -rf ${STAGE1_DIR}
     echo @@@BUILD_STEP build stage1 clang at $HOST_CLANG_REVISION@@@
     build_stage1_clang_impl && \
       ( echo $HOST_CLANG_REVISION > ${STAGE1_DIR}/host_clang_revision )
   fi
 }
 
 function build_stage1_clang_at_revison {
   build_clang_at_release_tag
 }
 
 function common_stage2_variables {
   cmake_stage2_common_options="\
     ${CMAKE_COMMON_OPTIONS} ${STAGE1_AS_COMPILER} -DLLVM_USE_LINKER=lld"
 }
 
 function build_stage2 {
   local sanitizer_name=$1
   echo @@@BUILD_STEP stage2/$sanitizer_name build libcxx@@@
 
   local libcxx_build_dir=libcxx_build_${sanitizer_name}
   local build_dir=llvm_build_${sanitizer_name}
   export STAGE2_DIR=${build_dir}
   local build_type="Release"
   local cmake_libcxx_cflags=
 
   common_stage2_variables
 
   local fno_sanitize_flag=
 
   if [ "$sanitizer_name" == "msan" ]; then
     export MSAN_SYMBOLIZER_PATH="${llvm_symbolizer_path}"
     llvm_use_sanitizer="Memory"
-    fsanitize_flag="-fsanitize=memory -fsanitize-memory-use-after-dtor -fsanitize-memory-param-retval"
+    fsanitize_flag="-fsanitize=memory -fsanitize-memory-use-after-dtor -fsanitize-memory-param-retval -Oz"
   elif [ "$sanitizer_name" == "msan_track_origins" ]; then
     export MSAN_SYMBOLIZER_PATH="${llvm_symbolizer_path}"
     llvm_use_sanitizer="MemoryWithOrigins"
-    fsanitize_flag="-fsanitize=memory -fsanitize-memory-track-origins -fsanitize-memory-use-after-dtor -fsanitize-memory-param-retval"
+    fsanitize_flag="-fsanitize=memory -fsanitize-memory-track-origins -fsanitize-memory-use-after-dtor -fsanitize-memory-param-retval -Oz"
   elif [ "$sanitizer_name" == "asan" ]; then
     export ASAN_SYMBOLIZER_PATH="${llvm_symbolizer_path}"
     export ASAN_OPTIONS="check_initialization_order=true:detect_stack_use_after_return=1"
     if [[ "$(arch)" == "aarch64" ]] ; then
       # FIXME: https://github.com/google/sanitizers/issues/703
       ASAN_OPTIONS+=":detect_leaks=0"
     else
       ASAN_OPTIONS+=":detect_leaks=1"
     fi
     llvm_use_sanitizer="Address"
     fsanitize_flag="-fsanitize=address"
     # FIXME: False ODR violations in libcxx tests.
     # https://github.com/google/sanitizers/issues/1017
     cmake_libcxx_cflags="-mllvm -asan-use-private-alias=1"
   elif [ "$sanitizer_name" == "hwasan" ]; then
     export HWASAN_SYMBOLIZER_PATH="${llvm_symbolizer_path}"
     export HWASAN_OPTIONS="abort_on_error=1"
     llvm_use_sanitizer="HWAddress"
     fsanitize_flag="-fsanitize=hwaddress -mllvm -hwasan-use-after-scope=1"
     # FIXME: Support globals with DSO https://github.com/llvm/llvm-project/issues/57206
     cmake_stage2_common_options+=" -DLLVM_ENABLE_PLUGINS=OFF"
   elif [ "$sanitizer_name" == "ubsan" ]; then
     export UBSAN_OPTIONS="external_symbolizer_path=${llvm_symbolizer_path}:print_stacktrace=1"
     llvm_use_sanitizer="Undefined"
     fsanitize_flag="-fsanitize=undefined"
     # FIXME: After switching to LLVM_ENABLE_RUNTIMES, vptr has infitine
     # recursion.
     fno_sanitize_flag+=" -fno-sanitize=vptr"
   else
     echo "Unknown sanitizer!"
     exit 1
   fi
 
   if [[ "${STAGE2_USE_LATE_EP:-}" != "1" ]] ; then
     fsanitize_flag+=" -mllvm -sanitizer-early-opt-ep"
   fi
 
   mkdir -p ${libcxx_build_dir}
   (cd ${libcxx_build_dir} && \
     cmake \
       ${cmake_stage2_common_options} \
       -DLLVM_ENABLE_RUNTIMES='libcxx;libcxxabi' \
       -DCMAKE_BUILD_TYPE=${build_type} \
       -DLLVM_USE_SANITIZER=${llvm_use_sanitizer} \
       -DCMAKE_C_FLAGS="${fsanitize_flag} ${cmake_libcxx_cflags} ${fno_sanitize_flag}" \
       -DCMAKE_CXX_FLAGS="${fsanitize_flag} ${cmake_libcxx_cflags} ${fno_sanitize_flag}" \
       $LLVM/../runtimes && \
     ninja cxx cxxabi) || build_failure
 
   local libcxx_runtime_path=$(dirname $(find ${ROOT}/${libcxx_build_dir} -name libc++.so))
   local sanitizer_ldflags="-Wl,--rpath=${libcxx_runtime_path} -L${libcxx_runtime_path}"
   local sanitizer_cflags="-nostdinc++ -isystem ${ROOT}/${libcxx_build_dir}/include -isystem ${ROOT}/${libcxx_build_dir}/include/c++/v1 $fsanitize_flag"
 
   echo @@@BUILD_STEP stage2/$sanitizer_name build@@@
 
   # See http://llvm.org/bugs/show_bug.cgi?id=19071, http://www.cmake.org/Bug/view.php?id=15264
   sanitizer_cflags+=" $sanitizer_ldflags -w"
 
   mkdir -p ${build_dir}
   local cmake_stage2_clang_options="-DLLVM_ENABLE_PROJECTS='clang;lld;clang-tools-extra;mlir'"
   if [[ "$(arch)" == "aarch64" ]] ; then
     # FIXME: clangd tests fail.
     cmake_stage2_clang_options="-DLLVM_ENABLE_PROJECTS='clang;lld;mlir'"
   fi
   (cd ${build_dir} && \
    cmake \
      ${cmake_stage2_common_options} \
      ${cmake_stage2_clang_options} \
      -DCMAKE_BUILD_TYPE=${build_type} \
      -DLLVM_USE_SANITIZER=${llvm_use_sanitizer} \
      -DLLVM_ENABLE_LIBCXX=ON \
      -DCMAKE_C_FLAGS="${sanitizer_cflags}" \
      -DCMAKE_CXX_FLAGS="${sanitizer_cflags}" \
      -DCMAKE_EXE_LINKER_FLAGS="${sanitizer_ldflags}" \
      $LLVM && \
    ninja) || build_failure
 }
 
 function build_stage2_msan {
   build_stage2 msan
 }
 
 function build_stage2_msan_track_origins {
   build_stage2 msan_track_origins
 }
 
 function build_stage2_asan {
   build_stage2 asan
 }
 
 function build_stage2_hwasan {
   build_stage2 hwasan
 }
 
 function build_stage2_ubsan {
   build_stage2 ubsan
 }
 
 function check_stage1 {
   local sanitizer_name=$1
 
   echo @@@BUILD_STEP stage1/$sanitizer_name check-sanitizer@@@
   ninja -C ${STAGE1_DIR} check-sanitizer || build_failure
 
   echo @@@BUILD_STEP stage1/$sanitizer_name check-${sanitizer_name}@@@
   ninja -C ${STAGE1_DIR} check-${sanitizer_name} || build_failure
 }
 
 function check_stage1_msan {
   check_stage1 msan
 }
 
 function check_stage1_asan {
   check_stage1 asan
 }
 
 function check_stage1_hwasan {
   check_stage1 hwasan
 }
 
 function check_stage1_ubsan {
   check_stage1 ubsan
 }
 
 function check_stage2 {
   local sanitizer_name=$1
 
   if [[ "${STAGE2_SKIP_TEST_CXX:-}" != "1" ]] ; then
     (
       # Very slow, run in background.
       LIT_OPTS+=" --timeout=1500"
       (
         # Very slow.
         export LIT_FILTER_OUT="modules_include.sh.cpp"
 
         LIT_FILTER_OUT+="|std/algorithms/alg.modifying.operations/alg.transform/ranges.transform.pass.cpp"
         LIT_FILTER_OUT+="|std/containers/sequences/deque/deque.modifiers/insert_iter_iter.pass.cpp"
         LIT_FILTER_OUT+="|std/numerics/rand/rand.dist/rand.dist.bern/rand.dist.bern.negbin/eval.pass.cpp"
         LIT_FILTER_OUT+="|std/numerics/rand/rand.dist/rand.dist.samp/rand.dist.samp.discrete/eval.pass.cpp"
         LIT_FILTER_OUT+="|std/utilities/charconv/charconv.msvc/test.pass.cpp"
         LIT_FILTER_OUT+="|std/utilities/format/format.functions/format_to_n.locale.pass.cpp"
         LIT_FILTER_OUT+="|std/utilities/format/format.functions/format_to_n.pass.cpp"
         LIT_FILTER_OUT+="|std/utilities/format/format.functions/format_to.locale.pass.cpp"
         LIT_FILTER_OUT+="|std/utilities/format/format.functions/format_to.pass.cpp"
         LIT_FILTER_OUT+="|std/utilities/format/format.functions/format.locale.pass.cpp"
         LIT_FILTER_OUT+="|std/utilities/format/format.functions/format.pass.cpp"
         LIT_FILTER_OUT+="|std/utilities/format/format.functions/formatted_size.locale.pass.cpp"
         LIT_FILTER_OUT+="|std/utilities/format/format.functions/formatted_size.pass.cpp"
         LIT_FILTER_OUT+="|std/utilities/format/format.functions/vformat"
         LIT_FILTER_OUT+="|std/utilities/variant/variant.visit/visit_return_type.pass.cpp"
         LIT_FILTER_OUT+="|std/utilities/variant/variant.visit/visit.pass.cpp"
 
         ninja -C libcxx_build_${sanitizer_name} check-cxx
       ) || build_failure
     ) &>check_cxx.log & 
 
     echo @@@BUILD_STEP stage2/$sanitizer_name check-cxxabi@@@
     (
       LIT_OPTS+=" --timeout=1100"
       if [[ "$(arch)" == "aarch64" && "$sanitizer_name" == "asan" ]] ; then
         # TODO: Investigate one leak and two slowest tests.
         export LIT_FILTER_OUT="test_vector2.pass.cpp|catch_multi_level_pointer.pass.cpp|guard_threaded_test.pass.cpp"
       fi
       if [[ "$(arch)" == "aarch64" && "$sanitizer_name" == "msan" ]] ; then
         # TODO: Investigate one slow tests.
         export LIT_FILTER_OUT="catch_multi_level_pointer.pass.cpp|guard_threaded_test.pass.cpp|test_demangle.pass.cpp"
       fi
       if [[ "$(arch)" == "aarch64" && "$sanitizer_name" == "hwasan" ]] ; then
         # TODO: Investigate one slow tests.
         export LIT_FILTER_OUT="catch_multi_level_pointer.pass.cpp|guard_threaded_test.pass.cpp|test_demangle.pass.cpp"
       fi
       ninja -C libcxx_build_${sanitizer_name} check-cxxabi
     ) || build_failure
   fi
 
   echo @@@BUILD_STEP stage2/$sanitizer_name check@@@
   ninja -C ${STAGE2_DIR} check-all || build_failure
 
   if [[ "${STAGE2_SKIP_TEST_CXX:-}" != "1" ]] ; then
     echo @@@BUILD_STEP stage2/$sanitizer_name check-cxx@@@
     wait
     sleep 5
     cat check_cxx.log
   fi
 }
 
 function check_stage2_msan {
   check_stage2 msan
 }
 
 function check_stage2_msan_track_origins {
   check_stage2 msan_track_origins
 }
 
 function check_stage2_asan {
   check_stage2 asan
 }
 
 function check_stage2_hwasan {
   check_stage2 hwasan
 }
 
 function check_stage2_ubsan {
   check_stage2 ubsan
 }
 
 function build_stage3 {
   local sanitizer_name=$1
   echo @@@BUILD_STEP build stage3/$sanitizer_name build@@@
 
   local build_dir=llvm_build2_${sanitizer_name}
 
   local clang_path=$ROOT/${STAGE2_DIR}/bin
   mkdir -p ${build_dir}
   local stage3_projects='clang;lld;clang-tools-extra'
   if [[ "$(arch)" == "aarch64" ]] ; then
     # FIXME: clangd tests fail.
     stage3_projects='clang;lld'
   fi
   (cd ${build_dir} && \
    cmake \
      ${CMAKE_COMMON_OPTIONS} \
      -DLLVM_ENABLE_PROJECTS="${stage3_projects}" \
      -DCMAKE_C_COMPILER=${clang_path}/clang \
      -DCMAKE_CXX_COMPILER=${clang_path}/clang++ \
      -DLLVM_USE_LINKER=lld \
      $LLVM && \
   ninja clang) || build_failure
 }
 
 function build_stage3_msan {
   build_stage3 msan
 }
 
 function build_stage3_msan_track_origins {
   build_stage3 msan_track_origins
 }
 
 function build_stage3_asan {
   build_stage3 asan
 }
 
 function build_stage3_hwasan {
   build_stage3 hwasan
 }
 
 function build_stage3_ubsan {
   build_stage3 ubsan
 }
 
 function check_stage3 {
   local sanitizer_name=$1
   echo @@@BUILD_STEP stage3/$sanitizer_name check@@@
 
   local build_dir=llvm_build2_${sanitizer_name}
 
   (cd ${build_dir} && env && ninja check-all) || build_failure
 }
 
 function check_stage3_msan {
   check_stage3 msan
 }
 
 function check_stage3_msan_track_origins {
   check_stage3 msan_track_origins
 }
 
 function check_stage3_asan {
   check_stage3 asan
 }
 
 function check_stage3_hwasan {
   check_stage3 hwasan
 }
 
 function check_stage3_ubsan {
   check_stage3 ubsan
 }
 
 function build_failure() {
   echo
   echo "How to reproduce locally: https://github.com/google/sanitizers/wiki/SanitizerBotReproduceBuild"
   echo
 
   sleep 5
   echo "@@@STEP_FAILURE@@@"
 }
 
 function build_exception() {
   echo
   echo "How to reproduce locally: https://github.com/google/sanitizers/wiki/SanitizerBotReproduceBuild"
   echo
 
   sleep 5
   echo "@@@STEP_EXCEPTION@@@"
 }