diff --git a/libcxx/utils/ci/macos-backdeployment.sh b/libcxx/utils/ci/macos-backdeployment.sh
index 71687c2f521eaa..4ed3bda2e3af27 100755
--- a/libcxx/utils/ci/macos-backdeployment.sh
+++ b/libcxx/utils/ci/macos-backdeployment.sh
@@ -4,14 +4,15 @@ set -ue
 
 function usage() {
   cat <<EOM
-$(basename ${0}) [-h|--help] --monorepo-root <MONOREPO-ROOT> --std <STD> --deployment-target <TARGET> --sdk-version <SDK-VERSION> [--libcxx-roots <DIR>] [--lit-args <ARGS...>] [--no-cleanup]
+$(basename ${0}) [-h|--help] --monorepo-root <MONOREPO-ROOT> --std <STD> --deployment-target <TARGET> [--libcxx-roots <DIR>] [--lit-args <ARGS...>] [--no-cleanup]
 
 This script is used to continually test the back-deployment use case of libc++ and libc++abi on MacOS.
 
+Specifically, this script runs the libc++ test suite against the just-built headers and linking against the just-built dylib, but it runs the tests against the dylibs for the given deployment target.
+
   --monorepo-root     Full path to the root of the LLVM monorepo. Both libc++ and libc++abi headers from the monorepo are used.
   --std               Version of the C++ Standard to run the tests under (c++03, c++11, etc..).
   --deployment-target The deployment target to run the tests for. This should be a version number of MacOS (e.g. 10.12). All MacOS versions until and including 10.9 are supported.
-  --sdk-version       The version of the SDK to test with. This should be a version number of MacOS (e.g. 10.12). We'll link against the libc++ dylib in that SDK, but we'll run against the one on the given deployment target. The SDK version must be no older than the deployment target.
   [--libcxx-roots]    The path to previous libc++/libc++abi dylibs to use for back-deployment testing. Those are normally downloaded automatically, but if specified, this option will override the directory used. The directory should have the same layout as the roots downloaded automatically.
   [--lit-args]        Additional arguments to pass to lit (optional). If there are multiple arguments, quote them to pass them as a single argument to this script.
   [--no-cleanup]      Do not cleanup the temporary directory that was used for testing at the end. This can be useful to debug failures. Make sure to clean up manually after.
@@ -19,14 +20,6 @@ This script is used to continually test the back-deployment use case of libc++ a
 EOM
 }
 
-function version-less-equal() {
-    [ "$1" = "$(echo -e "$1\n$2" | sort -V | head -n1)" ]
-}
-
-function version-less() {
-    [ "$1" = "$2" ] && return 1 || version-less-equal $1 $2
-}
-
 while [[ $# -gt 0 ]]; do
   case "$1" in
     --monorepo-root)
@@ -46,10 +39,6 @@ while [[ $# -gt 0 ]]; do
     DEPLOYMENT_TARGET="${2}"
     shift; shift
     ;;
-    --sdk-version)
-    MACOS_SDK_VERSION="${2}"
-    shift; shift
-    ;;
     --lit-args)
     ADDITIONAL_LIT_ARGS="${2}"
     shift; shift
@@ -77,16 +66,9 @@ done
 if [[ -z ${MONOREPO_ROOT+x} ]]; then echo "--monorepo-root is a required parameter"; usage; exit 1; fi
 if [[ -z ${STD+x} ]]; then echo "--std is a required parameter"; usage; exit 1; fi
 if [[ -z ${DEPLOYMENT_TARGET+x} ]]; then echo "--deployment-target is a required parameter"; usage; exit 1; fi
-if [[ -z ${MACOS_SDK_VERSION+x} ]]; then echo "--sdk-version is a required parameter"; usage; exit 1; fi
 if [[ -z ${ADDITIONAL_LIT_ARGS+x} ]]; then ADDITIONAL_LIT_ARGS=""; fi
 if [[ -z ${PREVIOUS_DYLIBS_DIR+x} ]]; then PREVIOUS_DYLIBS_DIR=""; fi
 
-if version-less "${MACOS_SDK_VERSION}" "${DEPLOYMENT_TARGET}"; then
-  echo "SDK version ${MACOS_SDK_VERSION} shouldn't be older than the deployment target (${DEPLOYMENT_TARGET})"
-  usage
-  exit 1
-fi
-
 TEMP_DIR="$(mktemp -d)"
 echo "Created temporary directory ${TEMP_DIR}"
 function cleanup {
@@ -121,12 +103,11 @@ mkdir -p "${LLVM_BUILD_DIR}"
 echo "@@@@@@"
 
 
-echo "@@@ Installing the latest libc++ headers @@@"
-ninja -C "${LLVM_BUILD_DIR}" install-cxx-headers
+echo "@@@ Building and installing libc++ and libc++abi @@@"
+ninja -C "${LLVM_BUILD_DIR}" install-cxx install-cxxabi
 echo "@@@@@@"
 
 
-# TODO: We should also link against the libc++abi.dylib that was shipped in the SDK
 if [[ ${PREVIOUS_DYLIBS_DIR} == "" ]]; then
   echo "@@@ Downloading dylibs for older deployment targets @@@"
   PREVIOUS_DYLIBS_DIR="${TEMP_DIR}/libcxx-dylibs"
@@ -137,7 +118,6 @@ fi
 
 LIBCXX_ROOT_ON_DEPLOYMENT_TARGET="${PREVIOUS_DYLIBS_DIR}/macOS/libc++/${DEPLOYMENT_TARGET}"
 LIBCXXABI_ROOT_ON_DEPLOYMENT_TARGET="${PREVIOUS_DYLIBS_DIR}/macOS/libc++abi/${DEPLOYMENT_TARGET}"
-LIBCXX_ROOT_IN_SDK="${PREVIOUS_DYLIBS_DIR}/macOS/libc++/${MACOS_SDK_VERSION}"
 
 # TODO: We need to also run the tests for libc++abi.
 echo "@@@ Running tests for libc++ @@@"
@@ -146,7 +126,7 @@ echo "@@@ Running tests for libc++ @@@"
                                  --param=cxx_headers="${LLVM_INSTALL_DIR}/include/c++/v1" \
                                  --param=std="${STD}" \
                                  --param=platform="macosx${DEPLOYMENT_TARGET}" \
-                                 --param=cxx_library_root="${LIBCXX_ROOT_IN_SDK}" \
+                                 --param=cxx_library_root="${LLVM_INSTALL_DIR}/lib" \
                                  --param=cxx_runtime_root="${LIBCXX_ROOT_ON_DEPLOYMENT_TARGET}" \
                                  --param=abi_library_path="${LIBCXXABI_ROOT_ON_DEPLOYMENT_TARGET}" \
                                  --param=use_system_cxx_lib="True" \