diff --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt
index 0aeb07ddbc1250..81aba149f39723 100644
--- a/libcxx/CMakeLists.txt
+++ b/libcxx/CMakeLists.txt
@@ -149,45 +149,19 @@ set(LIBCXX_LIBCPPABI_VERSION "2" CACHE STRING "Version of libc++abi's ABI to re-
                                                Note that this is not related to the version of libc++'s ABI itself!")
 
 # ABI Library options ---------------------------------------------------------
-set(LIBCXX_CXX_ABI "default" CACHE STRING
-    "Specify C++ ABI library to use.")
+set(LIBCXX_CXX_ABI "default" CACHE STRING "Specify C++ ABI library to use.")
 set(CXXABIS none default libcxxabi libcxxrt libstdc++ libsupc++ vcruntime)
 set_property(CACHE LIBCXX_CXX_ABI PROPERTY STRINGS ;${CXXABIS})
 
-# FIXME: This is a temporary hack to get the buildbots working while D63883 is in flight.
-# Without this all the bots fail while building libc++
-if (DEFINED ENV{USER})
-  if (("$ENV{USER}" STREQUAL "buildbot") OR (("$ENV{USER}" STREQUAL "llvmbb") OR ("$ENV{USER}" STREQUAL "buildslave")))
-    if (LIBCXX_CXX_ABI STREQUAL "libcxxabi" AND NOT DEFINED LIBCXX_CXX_ABI_INCLUDE_PATHS)
-      message(WARNING "OVERRIDING BUILDBOT CONFIG")
-      set(LIBCXX_CXX_ABI "default" CACHE STRING "FIXME" FORCE)
-    endif()
-  endif()
-endif()
 # Setup the default options if LIBCXX_CXX_ABI is not specified.
 if (LIBCXX_CXX_ABI STREQUAL "default")
-  find_path(
-    LIBCXX_LIBCXXABI_INCLUDES_INTERNAL cxxabi.h
-    PATHS ${LLVM_MAIN_SRC_DIR}/projects/libcxxabi/include
-          ${LLVM_MAIN_SRC_DIR}/runtimes/libcxxabi/include
-          ${LLVM_MAIN_SRC_DIR}/../libcxxabi/include
-    NO_DEFAULT_PATH
-    NO_CMAKE_FIND_ROOT_PATH
-  )
   if (LIBCXX_TARGETING_MSVC)
     # FIXME: Figure out how to configure the ABI library on Windows.
     set(LIBCXX_CXX_ABI_LIBNAME "vcruntime")
-  elseif ((NOT LIBCXX_STANDALONE_BUILD OR HAVE_LIBCXXABI) AND
-          IS_DIRECTORY "${LIBCXX_LIBCXXABI_INCLUDES_INTERNAL}")
-    set(LIBCXX_CXX_ABI_LIBNAME "libcxxabi")
-    set(LIBCXX_CXX_ABI_INCLUDE_PATHS "${LIBCXX_LIBCXXABI_INCLUDES_INTERNAL}")
-    set(LIBCXX_CXX_ABI_INTREE 1)
-  elseif (APPLE)
-    set(LIBCXX_CXX_ABI_LIBNAME "libcxxabi")
-    set(LIBCXX_CXX_ABI_SYSTEM 1)
   elseif (${CMAKE_SYSTEM_NAME} MATCHES "FreeBSD")
     set(LIBCXX_CXX_ABI_LIBNAME "libcxxrt")
-    set(LIBCXX_CXX_ABI_INCLUDE_PATHS "/usr/include/c++/v1")
+  elseif (NOT LIBCXX_STANDALONE_BUILD OR HAVE_LIBCXXABI)
+    set(LIBCXX_CXX_ABI_LIBNAME "libcxxabi")
   else()
     set(LIBCXX_CXX_ABI_LIBNAME "default")
   endif()
diff --git a/libcxx/cmake/Modules/HandleLibCXXABI.cmake b/libcxx/cmake/Modules/HandleLibCXXABI.cmake
index 2228fca1a551be..3cd9481de9c14f 100644
--- a/libcxx/cmake/Modules/HandleLibCXXABI.cmake
+++ b/libcxx/cmake/Modules/HandleLibCXXABI.cmake
@@ -102,24 +102,12 @@ if ("${LIBCXX_CXX_ABI_LIBNAME}" STREQUAL "libstdc++" OR
     "${_LIBSUPCXX_LIBNAME}" "${_LIBSUPCXX_LIBNAME}" "${_LIBSUPCXX_INCLUDE_FILES}" "bits"
     )
 elseif ("${LIBCXX_CXX_ABI_LIBNAME}" STREQUAL "libcxxabi")
-  if (LIBCXX_CXX_ABI_INTREE)
-    # Link against just-built "cxxabi" target.
-    set(CXXABI_SHARED_LIBNAME cxxabi_shared)
-    set(CXXABI_STATIC_LIBNAME cxxabi_static)
-  else()
-    # Assume c++abi is installed in the system, rely on -lc++abi link flag.
-    set(CXXABI_SHARED_LIBNAME "c++abi")
-    set(CXXABI_STATIC_LIBNAME "c++abi")
-  endif()
-  if (LIBCXX_CXX_ABI_SYSTEM)
-    set(HEADERS "")
-  else()
-    set(HEADERS "cxxabi.h;__cxxabi_config.h")
-  endif()
+  set(LIBCXX_CXX_ABI_INCLUDE_PATHS "${LIBCXX_SOURCE_DIR}/../libcxxabi/include")
   setup_abi_lib(
     "-DLIBCXX_BUILDING_LIBCXXABI"
-    "${CXXABI_SHARED_LIBNAME}" "${CXXABI_STATIC_LIBNAME}" "${HEADERS}" "")
+    "cxxabi_shared" "cxxabi_static" "cxxabi.h;__cxxabi_config.h" "")
 elseif ("${LIBCXX_CXX_ABI_LIBNAME}" STREQUAL "libcxxrt")
+  set(LIBCXX_CXX_ABI_INCLUDE_PATHS "/usr/include/c++/v1")
   setup_abi_lib(
     "-DLIBCXXRT"
     "cxxrt" "cxxrt" "cxxabi.h;unwind.h;unwind-arm.h;unwind-itanium.h" ""