Revert "[cmake] Use CMAKE_INSTALL_LIBDIR too"

This reverts commit f7a33090a91015836497c75f173775392ab0304d. Unfortunately this causes a number of failures that didn't show up in my local build.
2025-01-31 22:25:56 +00:00 · 2022-08-18 22:44:46 -04:00 · 2022-08-18 22:44:46 -04:00 · e941b031d3
commit e941b031d3
parent 481d67d310
67 changed files with 175 additions and 189 deletions
--- a/bolt/runtime/CMakeLists.txt
+++ b/bolt/runtime/CMakeLists.txt
@ -1,6 +1,5 @@
 cmake_minimum_required(VERSION 3.13.4)
 include(CheckIncludeFiles)
-include(GNUInstallDirs)

 set(CMAKE_CXX_EXTENSIONS OFF)
 set(CMAKE_CXX_STANDARD 17)
@ -33,8 +32,8 @@ target_include_directories(bolt_rt_instr PRIVATE ${CMAKE_CURRENT_BINARY_DIR})
 target_compile_options(bolt_rt_hugify PRIVATE ${BOLT_RT_FLAGS})
 target_include_directories(bolt_rt_hugify PRIVATE ${CMAKE_CURRENT_BINARY_DIR})

-install(TARGETS bolt_rt_instr DESTINATION "${CMAKE_INSTALL_LIBDIR}")
-install(TARGETS bolt_rt_hugify DESTINATION "${CMAKE_INSTALL_LIBDIR}")
+install(TARGETS bolt_rt_instr DESTINATION lib)
+install(TARGETS bolt_rt_hugify DESTINATION lib)

 if (CMAKE_CXX_COMPILER_ID MATCHES ".*Clang.*")
  add_library(bolt_rt_instr_osx STATIC
@ -45,5 +44,5 @@ if (CMAKE_CXX_COMPILER_ID MATCHES ".*Clang.*")
  target_compile_options(bolt_rt_instr_osx PRIVATE
    -target x86_64-apple-darwin19.6.0
    ${BOLT_RT_FLAGS})
-  install(TARGETS bolt_rt_instr_osx DESTINATION "${CMAKE_INSTALL_LIBDIR}")
+  install(TARGETS bolt_rt_instr_osx DESTINATION lib)
 endif()
--- a/clang/CMakeLists.txt
+++ b/clang/CMakeLists.txt
@ -37,7 +37,7 @@ if(CLANG_BUILT_STANDALONE)

  # They are used as destination of target generators.
  set(LLVM_RUNTIME_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin)
-  set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib)
+  set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib${LLVM_LIBDIR_SUFFIX})
  if(WIN32 OR CYGWIN)
    # DLL platform -- put DLLs into bin.
    set(LLVM_SHLIB_OUTPUT_INTDIR ${LLVM_RUNTIME_OUTPUT_INTDIR})
@ -72,8 +72,8 @@ if(CLANG_BUILT_STANDALONE)
  link_directories("${LLVM_LIBRARY_DIR}")

  set( CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin )
-  set( CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib )
-  set( CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib )
+  set( CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX} )
+  set( CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX} )

  if(LLVM_INCLUDE_TESTS)
    find_package(Python3 ${LLVM_MINIMUM_PYTHON_VERSION} REQUIRED
@ -303,6 +303,9 @@ if (NOT LLVM_LINK_LLVM_DYLIB AND CLANG_LINK_CLANG_DYLIB)
                      "LLVM_LINK_LLVM_DYLIB=OFF")
 endif()

+# The libdir suffix must exactly match whatever LLVM's configuration used.
+set(CLANG_LIBDIR_SUFFIX "${LLVM_LIBDIR_SUFFIX}")
+
 set(CLANG_TOOLS_INSTALL_DIR "${CMAKE_INSTALL_BINDIR}" CACHE PATH
    "Path for binary subdirectory (defaults to '${CMAKE_INSTALL_BINDIR}')")
 mark_as_advanced(CLANG_TOOLS_INSTALL_DIR)
@ -868,8 +871,6 @@ if(CLANG_BUILT_STANDALONE)
  process_llvm_pass_plugins()
 endif()

-get_filename_component(CLANG_INSTALL_LIBDIR_BASENAME "${CMAKE_INSTALL_LIBDIR}" NAME)
-
 configure_file(
  ${CLANG_SOURCE_DIR}/include/clang/Config/config.h.cmake
  ${CLANG_BINARY_DIR}/include/clang/Config/config.h)
--- a/clang/cmake/caches/Android-stage2.cmake
+++ b/clang/cmake/caches/Android-stage2.cmake
@ -4,7 +4,7 @@ set(CLANG_VENDOR Android CACHE STRING "")
 set(CMAKE_BUILD_TYPE Release CACHE STRING "")
 set(LLVM_ENABLE_THREADS OFF CACHE BOOL "")
 set(LLVM_ENABLE_ASSERTIONS ON CACHE BOOL "")
-set(CMAKE_INSTALL_LIBDIR "lib64" CACHE STRING "")
+set(LLVM_LIBDIR_SUFFIX 64 CACHE STRING "")
 set(LLVM_ENABLE_LIBCXX ON CACHE BOOL "")

 set(ANDROID_RUNTIMES_ENABLE_ASSERTIONS ON CACHE BOOL "")
--- a/clang/cmake/caches/Android.cmake
+++ b/clang/cmake/caches/Android.cmake
@ -13,7 +13,7 @@ set(HAVE_LIBCXXABI ON CACHE BOOL "")
 set(LLVM_BUILD_TOOLS OFF CACHE BOOL "")
 set(LLVM_ENABLE_ASSERTIONS ON CACHE BOOL "")
 set(LLVM_ENABLE_THREADS OFF CACHE BOOL "")
-set(CMAKE_INSTALL_LIBDIR "lib64" CACHE STRING "")
+set(LLVM_LIBDIR_SUFFIX 64 CACHE STRING "")
 set(LLVM_TOOL_CLANG_TOOLS_EXTRA_BUILD OFF CACHE BOOL "")
 set(LLVM_TOOL_OPENMP_BUILD OFF CACHE BOOL "")
 set(LLVM_ENABLE_LIBCXX ON CACHE BOOL "")
--- a/clang/cmake/modules/AddClang.cmake
+++ b/clang/cmake/modules/AddClang.cmake
@ -119,8 +119,8 @@ macro(add_clang_library name)
        install(TARGETS ${lib}
          COMPONENT ${lib}
          ${export_to_clangtargets}
-          LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
-          ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+          LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX}
+          ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX}
          RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}")

        if (NOT LLVM_ENABLE_IDE)
--- a/clang/cmake/modules/CMakeLists.txt
+++ b/clang/cmake/modules/CMakeLists.txt
@ -9,13 +9,13 @@ include(FindPrefixFromConfig)
 set(CLANG_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/clang" CACHE STRING
  "Path for CMake subdirectory for Clang (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/clang')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(clang_cmake_builddir "${CMAKE_BINARY_DIR}/lib/cmake/clang")
+set(clang_cmake_builddir "${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/clang")

 # Keep this in sync with llvm/cmake/CMakeLists.txt!
 set(LLVM_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/llvm" CACHE STRING
  "Path for CMake subdirectory for LLVM (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/llvm')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib/cmake/llvm")
+set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")

 get_property(CLANG_EXPORTS GLOBAL PROPERTY CLANG_EXPORTS)
 export(TARGETS ${CLANG_EXPORTS} FILE ${clang_cmake_builddir}/ClangTargets.cmake)
--- a/clang/include/clang/Config/config.h.cmake
+++ b/clang/include/clang/Config/config.h.cmake
@ -53,8 +53,8 @@
 /* Default architecture for SystemZ. */
 #define CLANG_SYSTEMZ_DEFAULT_ARCH "${CLANG_SYSTEMZ_DEFAULT_ARCH}"

-/* Multilib basename for libdir. */
-#define CLANG_INSTALL_LIBDIR_BASENAME "${CLANG_INSTALL_LIBDIR_BASENAME}"
+/* Multilib suffix for libdir. */
+#define CLANG_LIBDIR_SUFFIX "${CLANG_LIBDIR_SUFFIX}"

 /* Relative directory for resource files */
 #define CLANG_RESOURCE_DIR "${CLANG_RESOURCE_DIR}"
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@ -180,7 +180,7 @@ std::string Driver::GetResourcesPath(StringRef BinaryPath,
    // path of the embedding binary, which for LLVM binaries will be in bin/.
    // ../lib gets us to lib/ in both cases.
    P = llvm::sys::path::parent_path(Dir);
-    llvm::sys::path::append(P, CLANG_INSTALL_LIBDIR_BASENAME, "clang",
+    llvm::sys::path::append(P, Twine("lib") + CLANG_LIBDIR_SUFFIX, "clang",
                            CLANG_VERSION_STRING);
  }

--- a/clang/lib/Driver/ToolChains/CommonArgs.cpp
+++ b/clang/lib/Driver/ToolChains/CommonArgs.cpp
@ -502,8 +502,7 @@ void tools::addLTOOptions(const ToolChain &ToolChain, const ArgList &Args,

    SmallString<1024> Plugin;
    llvm::sys::path::native(
-        Twine(D.Dir) + "/../" CLANG_INSTALL_LIBDIR_BASENAME "/LLVMgold" +
-            Suffix,
+        Twine(D.Dir) + "/../lib" CLANG_LIBDIR_SUFFIX "/LLVMgold" + Suffix,
        Plugin);
    CmdArgs.push_back(Args.MakeArgString(Plugin));
  }
@ -659,7 +658,7 @@ void tools::addOpenMPRuntimeSpecificRPath(const ToolChain &TC,
    // runtime
    SmallString<256> DefaultLibPath =
        llvm::sys::path::parent_path(TC.getDriver().Dir);
-    llvm::sys::path::append(DefaultLibPath, CLANG_INSTALL_LIBDIR_BASENAME);
+    llvm::sys::path::append(DefaultLibPath, Twine("lib") + CLANG_LIBDIR_SUFFIX);
    CmdArgs.push_back("-rpath");
    CmdArgs.push_back(Args.MakeArgString(DefaultLibPath));
  }
@ -672,7 +671,7 @@ void tools::addOpenMPRuntimeLibraryPath(const ToolChain &TC,
  // runtime.
  SmallString<256> DefaultLibPath =
      llvm::sys::path::parent_path(TC.getDriver().Dir);
-  llvm::sys::path::append(DefaultLibPath, CLANG_INSTALL_LIBDIR_BASENAME);
+  llvm::sys::path::append(DefaultLibPath, Twine("lib") + CLANG_LIBDIR_SUFFIX);
  CmdArgs.push_back(Args.MakeArgString("-L" + DefaultLibPath));
 }

@ -1948,7 +1947,7 @@ void tools::AddStaticDeviceLibs(Compilation *C, const Tool *T,

  // Add path to lib-debug folders
  SmallString<256> DefaultLibPath = llvm::sys::path::parent_path(D.Dir);
-  llvm::sys::path::append(DefaultLibPath, CLANG_INSTALL_LIBDIR_BASENAME);
+  llvm::sys::path::append(DefaultLibPath, Twine("lib") + CLANG_LIBDIR_SUFFIX);
  LibraryPaths.emplace_back(DefaultLibPath.c_str());

  // Build list of Static Device Libraries SDLs specified by -l option
@ -2077,7 +2076,7 @@ void tools::addOpenMPDeviceRTL(const Driver &D,

  // Add path to clang lib / lib64 folder.
  SmallString<256> DefaultLibPath = llvm::sys::path::parent_path(D.Dir);
-  llvm::sys::path::append(DefaultLibPath, CLANG_INSTALL_LIBDIR_BASENAME);
+  llvm::sys::path::append(DefaultLibPath, Twine("lib") + CLANG_LIBDIR_SUFFIX);
  LibraryPaths.emplace_back(DefaultLibPath.c_str());

  // Add user defined library paths from LIBRARY_PATH.
--- a/clang/lib/Driver/ToolChains/Cuda.cpp
+++ b/clang/lib/Driver/ToolChains/Cuda.cpp
@ -592,7 +592,7 @@ void NVPTX::OpenMPLinker::ConstructJob(Compilation &C, const JobAction &JA,
  // Add paths for the default clang library path.
  SmallString<256> DefaultLibPath =
      llvm::sys::path::parent_path(TC.getDriver().Dir);
-  llvm::sys::path::append(DefaultLibPath, CLANG_INSTALL_LIBDIR_BASENAME);
+  llvm::sys::path::append(DefaultLibPath, "lib" CLANG_LIBDIR_SUFFIX);
  CmdArgs.push_back(Args.MakeArgString(Twine("-L") + DefaultLibPath));

  for (const auto &II : Inputs) {
--- a/clang/lib/Headers/CMakeLists.txt
+++ b/clang/lib/Headers/CMakeLists.txt
@ -420,7 +420,7 @@ add_header_target("openmp-resource-headers" ${openmp_wrapper_files})
 add_header_target("windows-resource-headers" ${windows_only_files})
 add_header_target("utility-resource-headers" ${utility_files})

-set(header_install_dir ${CMAKE_INSTALL_LIBDIR}/clang/${CLANG_VERSION}/include)
+set(header_install_dir lib${LLVM_LIBDIR_SUFFIX}/clang/${CLANG_VERSION}/include)

 #############################################################
 # Install rules for the catch-all clang-resource-headers target
--- a/clang/runtime/CMakeLists.txt
+++ b/clang/runtime/CMakeLists.txt
@ -84,12 +84,10 @@ if(LLVM_BUILD_EXTERNAL_COMPILER_RT AND EXISTS ${COMPILER_RT_SRC_ROOT}/)
               -DLLVM_LIT_ARGS=${LLVM_LIT_ARGS}
               -DCOMPILER_RT_OUTPUT_DIR=${LLVM_LIBRARY_OUTPUT_INTDIR}/clang/${CLANG_VERSION}
               -DCOMPILER_RT_EXEC_OUTPUT_DIR=${LLVM_RUNTIME_OUTPUT_INTDIR}
-               -DCOMPILER_RT_INSTALL_PATH:PATH=lib/clang/${CLANG_VERSION}
+               -DCOMPILER_RT_INSTALL_PATH:PATH=lib${LLVM_LIBDIR_SUFFIX}/clang/${CLANG_VERSION}
               -DCOMPILER_RT_INCLUDE_TESTS=${LLVM_INCLUDE_TESTS}
-               -DCMAKE_INSTALL_PREFIX="${CMAKE_INSTALL_PREFIX}"
-               -DCMAKE_INSTALL_BINDIR="${CMAKE_INSTALL_BINDIR}"
-               -DCMAKE_INSTALL_LIBDIR="${CMAKE_INSTALL_LIBDIR}"
-               -DCMAKE_INSTALL_INCLUDEDIR="${CMAKE_INSTALL_INCLUDEDIR}"
+               -DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX}
+               -DLLVM_LIBDIR_SUFFIX=${LLVM_LIBDIR_SUFFIX}
               -DLLVM_RUNTIME_OUTPUT_INTDIR=${LLVM_RUNTIME_OUTPUT_INTDIR}
               -DCMAKE_OSX_DEPLOYMENT_TARGET=${CMAKE_OSX_DEPLOYMENT_TARGET}
               -DCMAKE_OSX_SYSROOT:PATH=${CMAKE_OSX_SYSROOT}
--- a/clang/tools/libclang/CMakeLists.txt
+++ b/clang/tools/libclang/CMakeLists.txt
@ -180,7 +180,7 @@ foreach(PythonVersion ${CLANG_PYTHON_BINDINGS_VERSIONS})
          COMPONENT
            libclang-python-bindings
          DESTINATION
-            "${CMAKE_INSTALL_LIBDIR}/python${PythonVersion}/site-packages")
+            "lib${LLVM_LIBDIR_SUFFIX}/python${PythonVersion}/site-packages")
 endforeach()
 if(NOT LLVM_ENABLE_IDE)
  add_custom_target(libclang-python-bindings)
--- a/clang/tools/scan-build-py/CMakeLists.txt
+++ b/clang/tools/scan-build-py/CMakeLists.txt
@ -88,7 +88,7 @@ foreach(lib ${LibScanbuild})
                     DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/lib/libscanbuild/${lib})
  list(APPEND Depends ${CMAKE_BINARY_DIR}/lib/libscanbuild/${lib})
  install(PROGRAMS lib/libscanbuild/${lib}
-          DESTINATION "${CMAKE_INSTALL_LIBDIR}/libscanbuild"
+          DESTINATION lib/libscanbuild
          COMPONENT scan-build-py)
 endforeach()

@ -106,7 +106,7 @@ foreach(resource ${LibScanbuildResources})
                     DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/lib/libscanbuild/resources/${resource})
  list(APPEND Depends ${CMAKE_BINARY_DIR}/lib/libscanbuild/resources/${resource})
  install(PROGRAMS lib/libscanbuild/resources/${resource}
-          DESTINATION "${CMAKE_INSTALL_LIBDIR}/libscanbuild/resources"
+          DESTINATION lib/libscanbuild/resources
          COMPONENT scan-build-py)
 endforeach()

@ -122,7 +122,7 @@ foreach(lib ${LibEar})
                     DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/lib/libear/${lib})
  list(APPEND Depends ${CMAKE_BINARY_DIR}/lib/libear/${lib})
  install(PROGRAMS lib/libear/${lib}
-          DESTINATION "${CMAKE_INSTALL_LIBDIR}/libear"
+          DESTINATION lib/libear
          COMPONENT scan-build-py)
 endforeach()

--- a/cmake/Modules/GNUInstallPackageDir.cmake
+++ b/cmake/Modules/GNUInstallPackageDir.cmake
@ -29,5 +29,5 @@ macro(_GNUInstallPackageDir_cache_path var default description)
  _GNUInstallPackageDir_cache_convert_to_path("${var}" "${description}")
 endmacro()

-_GNUInstallPackageDir_cache_path(CMAKE_INSTALL_PACKAGEDIR "${CMAKE_INSTALL_LIBDIR}/cmake"
+_GNUInstallPackageDir_cache_path(CMAKE_INSTALL_PACKAGEDIR "lib${LLVM_LIBDIR_SUFFIX}/cmake"
  "Directories containing installed CMake modules (lib/cmake)")
--- a/compiler-rt/cmake/Modules/CompilerRTAIXUtils.cmake
+++ b/compiler-rt/cmake/Modules/CompilerRTAIXUtils.cmake
@ -62,7 +62,7 @@ macro(archive_aix_libatomic name libname)
    # setting _install_rpath on AIX for reference.
    if(LLVM_LIBRARY_OUTPUT_INTDIR AND CMAKE_INSTALL_PREFIX)
      set(output_dir "${LLVM_LIBRARY_OUTPUT_INTDIR}")
-      set(install_dir "${CMAKE_INSTALL_LIBDIR}")
+      set(install_dir "${CMAKE_INSTALL_PREFIX}/lib${LLVM_LIBDIR_SUFFIX}")
    else()
      get_compiler_rt_output_dir(${COMPILER_RT_DEFAULT_TARGET_ARCH} output_dir)
      get_compiler_rt_install_dir(${COMPILER_RT_DEFAULT_TARGET_ARCH} install_dir)
--- a/compiler-rt/cmake/Modules/CompilerRTUtils.cmake
+++ b/compiler-rt/cmake/Modules/CompilerRTUtils.cmake
@ -377,7 +377,7 @@ macro(load_llvm_config)
      file(TO_CMAKE_PATH ${LLVM_CMAKE_DIR_FROM_LLVM_CONFIG} LLVM_CMAKE_DIR)
    else()
      file(TO_CMAKE_PATH ${LLVM_BINARY_DIR} LLVM_BINARY_DIR_CMAKE_STYLE)
-      set(LLVM_CMAKE_DIR "${LLVM_BINARY_DIR_CMAKE_STYLE}/lib/cmake/llvm")
+      set(LLVM_CMAKE_DIR "${LLVM_BINARY_DIR_CMAKE_STYLE}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")
    endif()

    set(LLVM_CMAKE_INCLUDE_FILE "${LLVM_CMAKE_DIR}/LLVMConfig.cmake")
@ -393,7 +393,7 @@ macro(load_llvm_config)
    unset(LLVM_CMAKE_INCLUDE_FILE)

    set(LLVM_LIBRARY_OUTPUT_INTDIR
-      ${LLVM_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib)
+      ${LLVM_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib${LLVM_LIBDIR_SUFFIX})
  endif()

  # Finally set the cache variable now that `llvm-config` has also had a chance
--- a/compiler-rt/cmake/base-config-ix.cmake
+++ b/compiler-rt/cmake/base-config-ix.cmake
@ -45,7 +45,7 @@ if (LLVM_TREE_AVAILABLE)
  # Setup the paths where compiler-rt runtimes and headers should be stored.
  set(COMPILER_RT_OUTPUT_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/clang/${CLANG_VERSION})
  set(COMPILER_RT_EXEC_OUTPUT_DIR ${LLVM_RUNTIME_OUTPUT_INTDIR})
-  set(COMPILER_RT_INSTALL_PATH "${CMAKE_INSTALL_LIBDIR}/clang/${CLANG_VERSION}")
+  set(COMPILER_RT_INSTALL_PATH lib${LLVM_LIBDIR_SUFFIX}/clang/${CLANG_VERSION})
  option(COMPILER_RT_INCLUDE_TESTS "Generate and build compiler-rt unit tests."
         ${LLVM_INCLUDE_TESTS})
  option(COMPILER_RT_ENABLE_WERROR "Fail and stop if warning is triggered"
@ -97,30 +97,25 @@ if(NOT DEFINED COMPILER_RT_OS_DIR)
    string(TOLOWER ${CMAKE_SYSTEM_NAME} COMPILER_RT_OS_DIR)
  endif()
 endif()
-
 if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
  set(COMPILER_RT_OUTPUT_LIBRARY_DIR
    ${COMPILER_RT_OUTPUT_DIR}/lib)
-  # Don't use "${CMAKE_INSTALL_LIBDIR}", because the intended use-case is that
-  # "${COMPILER_RT_INSTALL_PATH}" is already non-trival and probably includes
-  # "${CMAKE_INSTALL_LIBDIR}".
-  extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" "lib")
-else()
+  extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" lib)
+  set(COMPILER_RT_INSTALL_LIBRARY_DIR "${default_install_path}" CACHE PATH
+    "Path where built compiler-rt libraries should be installed.")
+else(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
  set(COMPILER_RT_OUTPUT_LIBRARY_DIR
    ${COMPILER_RT_OUTPUT_DIR}/lib/${COMPILER_RT_OS_DIR})
-  extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" "${CMAKE_INSTALL_LIBDIR}/${COMPILER_RT_OS_DIR}")
+  extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" "lib/${COMPILER_RT_OS_DIR}")
+  set(COMPILER_RT_INSTALL_LIBRARY_DIR "${default_install_path}" CACHE PATH
+    "Path where built compiler-rt libraries should be installed.")
 endif()
-set(COMPILER_RT_INSTALL_LIBRARY_DIR "${default_install_path}" CACHE PATH
-  "Path where built compiler-rt libraries should be installed.")
-
 extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" "${CMAKE_INSTALL_BINDIR}")
 set(COMPILER_RT_INSTALL_BINARY_DIR "${default_install_path}" CACHE PATH
  "Path where built compiler-rt executables should be installed.")
-
 extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" "${CMAKE_INSTALL_INCLUDEDIR}")
 set(COMPILER_RT_INSTALL_INCLUDE_DIR "${default_install_path}" CACHE PATH
  "Path where compiler-rt headers should be installed.")
-
 extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" "${CMAKE_INSTALL_DATADIR}")
 set(COMPILER_RT_INSTALL_DATA_DIR "${default_install_path}" CACHE PATH
  "Path where compiler-rt data files should be installed.")
--- a/compiler-rt/docs/BuildingCompilerRT.rst
+++ b/compiler-rt/docs/BuildingCompilerRT.rst
@ -79,3 +79,14 @@ Compiler-RT specific options

  Path where Compiler-RT data should be installed. If a relative
  path, relative to ``COMPILER_RT_INSTALL_PATH``.
+
+.. _LLVM-specific variables:
+
+LLVM-specific options
+---------------------
+
+.. option:: LLVM_LIBDIR_SUFFIX:STRING
+
+  Extra suffix to append to the directory where libraries are to be
+  installed. On a 64-bit architecture, one could use ``-DLLVM_LIBDIR_SUFFIX=64``
+  to install libraries to ``/usr/lib64``.
--- a/flang/CMakeLists.txt
+++ b/flang/CMakeLists.txt
@ -129,9 +129,9 @@ if (FLANG_STANDALONE_BUILD)

  set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
  set(CMAKE_LIBRARY_OUTPUT_DIRECTORY
-    ${CMAKE_BINARY_DIR}/lib)
+    ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX})
  set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY
-    ${CMAKE_BINARY_DIR}/lib)
+    ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX})

  set(BACKEND_PACKAGE_STRING "LLVM ${LLVM_PACKAGE_VERSION}")
  set(LLVM_EXTERNAL_LIT "${LLVM_TOOLS_BINARY_DIR}/llvm-lit" CACHE STRING "Command used to spawn lit")
--- a/flang/cmake/modules/AddFlang.cmake
+++ b/flang/cmake/modules/AddFlang.cmake
@ -71,8 +71,8 @@ macro(add_flang_library name)
      install(TARGETS ${name}
        COMPONENT ${name}
        ${export_to_flangtargets}
-        LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
-        ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+        LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX}
+        ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX}
        RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}")

      if (NOT LLVM_ENABLE_IDE)
--- a/flang/cmake/modules/CMakeLists.txt
+++ b/flang/cmake/modules/CMakeLists.txt
@ -8,13 +8,13 @@ include(FindPrefixFromConfig)
 set(FLANG_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/flang" CACHE STRING
  "Path for CMake subdirectory for Flang (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/flang')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(flang_cmake_builddir "${CMAKE_BINARY_DIR}/lib/cmake/flang")
+set(flang_cmake_builddir "${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/flang")

 # Keep this in sync with llvm/cmake/CMakeLists.txt!
 set(LLVM_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/llvm" CACHE STRING
  "Path for CMake subdirectory for LLVM (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/llvm')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib/cmake/llvm")
+set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")

 get_property(FLANG_EXPORTS GLOBAL PROPERTY FLANG_EXPORTS)
 export(TARGETS ${FLANG_EXPORTS} FILE ${flang_cmake_builddir}/FlangTargets.cmake)
--- a/libc/CMakeLists.txt
+++ b/libc/CMakeLists.txt
@ -1,7 +1,5 @@
 cmake_minimum_required(VERSION 3.13.4)

-include(GNUInstallDirs)
-
 # Default to C++17
 set(CMAKE_CXX_STANDARD 17)

--- a/libc/lib/CMakeLists.txt
+++ b/libc/lib/CMakeLists.txt
@ -5,9 +5,9 @@ add_entrypoint_library(
 )

 if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR)
-  set(LIBC_INSTALL_LIBRARY_DIR ${CMAKE_INSTALL_LIBDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
+  set(LIBC_INSTALL_LIBRARY_DIR lib${LLVM_LIBDIR_SUFFIX}/${LLVM_DEFAULT_TARGET_TRIPLE})
 else()
-  set(LIBC_INSTALL_LIBRARY_DIR ${CMAKE_INSTALL_LIBDIR})
+  set(LIBC_INSTALL_LIBRARY_DIR lib${LLVM_LIBDIR_SUFFIX})
 endif()

 install(
--- a/libcxx/CMakeLists.txt
+++ b/libcxx/CMakeLists.txt
@ -151,6 +151,8 @@ if (LIBCXX_BENCHMARK_NATIVE_STDLIB)
 endif()

 option(LIBCXX_INCLUDE_DOCS "Build the libc++ documentation." ${LLVM_INCLUDE_DOCS})
+set(LIBCXX_LIBDIR_SUFFIX "${LLVM_LIBDIR_SUFFIX}" CACHE STRING
+    "Define suffix of library directory name (32/64)")
 option(LIBCXX_INSTALL_HEADERS "Install the libc++ headers." ON)
 option(LIBCXX_INSTALL_LIBRARY "Install the libc++ library." ON)
 cmake_dependent_option(LIBCXX_INSTALL_STATIC_LIBRARY
@ -417,7 +419,7 @@ if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
  set(LIBCXX_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
  set(LIBCXX_GENERATED_INCLUDE_DIR "${LLVM_BINARY_DIR}/include/c++/v1")
  set(LIBCXX_GENERATED_INCLUDE_TARGET_DIR "${LLVM_BINARY_DIR}/include/${LLVM_DEFAULT_TARGET_TRIPLE}/c++/v1")
-  set(LIBCXX_INSTALL_LIBRARY_DIR ${CMAKE_INSTALL_LIBDIR}/${LLVM_DEFAULT_TARGET_TRIPLE} CACHE PATH
+  set(LIBCXX_INSTALL_LIBRARY_DIR lib${LLVM_LIBDIR_SUFFIX}/${LLVM_DEFAULT_TARGET_TRIPLE} CACHE PATH
      "Path where built libc++ libraries should be installed.")
  set(LIBCXX_INSTALL_INCLUDE_TARGET_DIR "${CMAKE_INSTALL_INCLUDEDIR}/${LLVM_DEFAULT_TARGET_TRIPLE}/c++/v1" CACHE PATH
      "Path where target-specific libc++ headers should be installed.")
@ -430,11 +432,11 @@ else()
    set(LIBCXX_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR})
    set(LIBCXX_GENERATED_INCLUDE_DIR "${LLVM_BINARY_DIR}/include/c++/v1")
  else()
-    set(LIBCXX_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib)
+    set(LIBCXX_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LIBCXX_LIBDIR_SUFFIX})
    set(LIBCXX_GENERATED_INCLUDE_DIR "${CMAKE_BINARY_DIR}/include/c++/v1")
  endif()
  set(LIBCXX_GENERATED_INCLUDE_TARGET_DIR "${LIBCXX_GENERATED_INCLUDE_DIR}")
-  set(LIBCXX_INSTALL_LIBRARY_DIR "${CMAKE_INSTALL_LIBDIR}" CACHE PATH
+  set(LIBCXX_INSTALL_LIBRARY_DIR lib${LIBCXX_LIBDIR_SUFFIX} CACHE PATH
      "Path where built libc++ libraries should be installed.")
  set(LIBCXX_INSTALL_INCLUDE_TARGET_DIR "${LIBCXX_INSTALL_INCLUDE_DIR}" CACHE PATH
      "Path where target-specific libc++ headers should be installed.")
--- a/libcxx/docs/BuildingLibcxx.rst
+++ b/libcxx/docs/BuildingLibcxx.rst
@ -235,6 +235,11 @@ libc++ specific options
  Build libc++ as a static library. Either `LIBCXX_ENABLE_SHARED` or
  `LIBCXX_ENABLE_STATIC` has to be enabled.

+.. option:: LIBCXX_LIBDIR_SUFFIX:STRING
+
+  Extra suffix to append to the directory where libraries are to be installed.
+  This option overrides `LLVM_LIBDIR_SUFFIX`.
+
 .. option:: LIBCXX_HERMETIC_STATIC_LIBRARY:BOOL

  **Default**: ``OFF``
@ -262,7 +267,7 @@ libc++ specific options

 .. option:: LIBCXX_INSTALL_LIBRARY_DIR:PATH

-  **Default**: ``lib``
+  **Default**: ``lib${LIBCXX_LIBDIR_SUFFIX}``

  Path where built libc++ libraries should be installed. If a relative path,
  relative to ``CMAKE_INSTALL_PREFIX``.
@ -425,6 +430,12 @@ The following options allow building libc++ for a different ABI version.
 LLVM-specific options
 ---------------------

+.. option:: LLVM_LIBDIR_SUFFIX:STRING
+
+  Extra suffix to append to the directory where libraries are to be
+  installed. On a 64-bit architecture, one could use ``-DLLVM_LIBDIR_SUFFIX=64``
+  to install libraries to ``/usr/lib64``.
+
 .. option:: LLVM_BUILD_32_BITS:BOOL

  Build 32-bits executables and libraries on 64-bits systems. This option is
--- a/libcxxabi/CMakeLists.txt
+++ b/libcxxabi/CMakeLists.txt
@ -74,6 +74,8 @@ if (LIBCXXABI_BUILD_32_BITS)
 endif()

 option(LIBCXXABI_INCLUDE_TESTS "Generate build targets for the libc++abi unit tests." ${LLVM_INCLUDE_TESTS})
+set(LIBCXXABI_LIBDIR_SUFFIX "${LLVM_LIBDIR_SUFFIX}" CACHE STRING
+    "Define suffix of library directory name (32/64)")
 option(LIBCXXABI_INSTALL_HEADERS "Install the libc++abi headers." ON)
 option(LIBCXXABI_INSTALL_LIBRARY "Install the libc++abi library." ON)

@ -185,7 +187,7 @@ set(LIBCXXABI_INSTALL_RUNTIME_DIR "${CMAKE_INSTALL_BINDIR}" CACHE PATH
 if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
  set(LIBCXXABI_HEADER_DIR ${LLVM_BINARY_DIR})
  set(LIBCXXABI_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
-  set(LIBCXXABI_INSTALL_LIBRARY_DIR ${CMAKE_INSTALL_LIBDIR}/${LLVM_DEFAULT_TARGET_TRIPLE} CACHE PATH
+  set(LIBCXXABI_INSTALL_LIBRARY_DIR lib${LLVM_LIBDIR_SUFFIX}/${LLVM_DEFAULT_TARGET_TRIPLE} CACHE PATH
      "Path where built libc++abi libraries should be installed.")
  if(LIBCXX_LIBDIR_SUBDIR)
    string(APPEND LIBCXXABI_LIBRARY_DIR /${LIBCXXABI_LIBDIR_SUBDIR})
@ -197,9 +199,9 @@ else()
    set(LIBCXXABI_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR})
  else()
    set(LIBCXXABI_HEADER_DIR ${CMAKE_BINARY_DIR})
-    set(LIBCXXABI_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib)
+    set(LIBCXXABI_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LIBCXXABI_LIBDIR_SUFFIX})
  endif()
-  set(LIBCXXABI_INSTALL_LIBRARY_DIR "${CMAKE_INSTALL_LIBDIR}" CACHE PATH
+  set(LIBCXXABI_INSTALL_LIBRARY_DIR lib${LIBCXXABI_LIBDIR_SUFFIX} CACHE PATH
      "Path where built libc++abi libraries should be installed.")
 endif()

--- a/libunwind/CMakeLists.txt
+++ b/libunwind/CMakeLists.txt
@ -51,6 +51,8 @@ option(LIBUNWIND_USE_FRAME_HEADER_CACHE "Cache frame headers for unwinding. Requ
 option(LIBUNWIND_REMEMBER_HEAP_ALLOC "Use heap instead of the stack for .cfi_remember_state." OFF)
 option(LIBUNWIND_INSTALL_HEADERS "Install the libunwind headers." OFF)

+set(LIBUNWIND_LIBDIR_SUFFIX "${LLVM_LIBDIR_SUFFIX}" CACHE STRING
+    "Define suffix of library directory name (32/64)")
 option(LIBUNWIND_INSTALL_LIBRARY "Install the libunwind library." ON)
 cmake_dependent_option(LIBUNWIND_INSTALL_STATIC_LIBRARY
  "Install the static libunwind library." ON
@ -115,7 +117,7 @@ set(LIBUNWIND_INSTALL_RUNTIME_DIR "${CMAKE_INSTALL_BINDIR}" CACHE PATH

 if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
  set(LIBUNWIND_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
-  set(LIBUNWIND_INSTALL_LIBRARY_DIR ${CMAKE_INSTALL_LIBDIR}/${LLVM_DEFAULT_TARGET_TRIPLE} CACHE PATH
+  set(LIBUNWIND_INSTALL_LIBRARY_DIR lib${LLVM_LIBDIR_SUFFIX}/${LLVM_DEFAULT_TARGET_TRIPLE} CACHE PATH
      "Path where built libunwind libraries should be installed.")
  if(LIBCXX_LIBDIR_SUBDIR)
    string(APPEND LIBUNWIND_LIBRARY_DIR /${LIBUNWIND_LIBDIR_SUBDIR})
@ -125,9 +127,9 @@ else()
  if(LLVM_LIBRARY_OUTPUT_INTDIR)
    set(LIBUNWIND_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR})
  else()
-    set(LIBUNWIND_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib)
+    set(LIBUNWIND_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LIBUNWIND_LIBDIR_SUFFIX})
  endif()
-  set(LIBUNWIND_INSTALL_LIBRARY_DIR "${CMAKE_INSTALL_LIBDIR}" CACHE PATH
+  set(LIBUNWIND_INSTALL_LIBRARY_DIR lib${LIBUNWIND_LIBDIR_SUFFIX} CACHE PATH
      "Path where built libunwind libraries should be installed.")
 endif()

--- a/libunwind/docs/BuildingLibunwind.rst
+++ b/libunwind/docs/BuildingLibunwind.rst
@ -144,7 +144,7 @@ libunwind specific options

 .. option:: LIBUNWIND_INSTALL_LIBRARY_DIR:PATH

-  **Default**: ``lib``
+  **Default**: ``lib${LIBUNWIND_LIBDIR_SUFFIX}``

  Path where built libunwind libraries should be installed. If a relative path,
  relative to ``CMAKE_INSTALL_PREFIX``.
--- a/lld/CMakeLists.txt
+++ b/lld/CMakeLists.txt
@ -30,7 +30,7 @@ if(LLD_BUILT_STANDALONE)

  # They are used as destination of target generators.
  set(LLVM_RUNTIME_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin)
-  set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib)
+  set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib${LLVM_LIBDIR_SUFFIX})

  include(AddLLVM)
  include(TableGen)
--- a/lld/cmake/modules/AddLLD.cmake
+++ b/lld/cmake/modules/AddLLD.cmake
@ -18,8 +18,8 @@ macro(add_lld_library name)
    install(TARGETS ${name}
      COMPONENT ${name}
      ${export_to_lldtargets}
-      LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
-      ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+      LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX}
+      ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX}
      RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}")

    if (${ARG_SHARED} AND NOT CMAKE_CONFIGURATION_TYPES)
--- a/lld/cmake/modules/CMakeLists.txt
+++ b/lld/cmake/modules/CMakeLists.txt
@ -8,13 +8,13 @@ include(FindPrefixFromConfig)
 set(LLD_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/lld" CACHE STRING
  "Path for CMake subdirectory for LLD (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/lld')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(lld_cmake_builddir "${CMAKE_BINARY_DIR}/lib/cmake/lld")
+set(lld_cmake_builddir "${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/lld")

 # Keep this in sync with llvm/cmake/CMakeLists.txt!
 set(LLVM_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/llvm" CACHE STRING
  "Path for CMake subdirectory for LLVM (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/llvm')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib/cmake/llvm")
+set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")

 get_property(LLD_EXPORTS GLOBAL PROPERTY LLD_EXPORTS)
 export(TARGETS ${LLD_EXPORTS} FILE ${lld_cmake_builddir}/LLDTargets.cmake)
--- a/lldb/cmake/modules/AddLLDB.cmake
+++ b/lldb/cmake/modules/AddLLDB.cmake
@ -109,7 +109,7 @@ function(add_lldb_library name)
  endif()

  if(PARAM_SHARED)
-    set(install_dest "${CMAKE_INSTALL_LIBDIR}")
+    set(install_dest lib${LLVM_LIBDIR_SUFFIX})
    if(PARAM_INSTALL_PREFIX)
      set(install_dest ${PARAM_INSTALL_PREFIX})
    endif()
--- a/lldb/cmake/modules/LLDBConfig.cmake
+++ b/lldb/cmake/modules/LLDBConfig.cmake
@ -276,7 +276,7 @@ if (NOT TARGET clang-resource-headers)
  # could be and pick the first that exists.
  foreach(CANDIDATE "${Clang_DIR}/../.." "${LLVM_DIR}" "${LLVM_LIBRARY_DIRS}"
                    "${LLVM_BUILD_LIBRARY_DIR}"
-                    "${LLVM_BINARY_DIR}/lib")
+                    "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}")
    # Build the resource directory path by appending 'clang/<version number>'.
    set(CANDIDATE_RESOURCE_DIR "${CANDIDATE}/clang/${LLDB_CLANG_RESOURCE_DIR_NAME}")
    if (IS_DIRECTORY "${CANDIDATE_RESOURCE_DIR}")
--- a/lldb/cmake/modules/LLDBGenerateConfig.cmake
+++ b/lldb/cmake/modules/LLDBGenerateConfig.cmake
@ -19,8 +19,6 @@ check_cxx_symbol_exists(__NR_process_vm_readv "sys/syscall.h" HAVE_NR_PROCESS_VM

 check_library_exists(compression compression_encode_buffer "" HAVE_LIBCOMPRESSION)

-get_filename_component(LLDB_INSTALL_LIBDIR_BASENAME "${CMAKE_INSTALL_LIBDIR}" NAME)
-
 # These checks exist in LLVM's configuration, so I want to match the LLVM names
 # so that the check isn't duplicated, but we translate them into the LLDB names
 # so that I don't have to change all the uses at the moment.
--- a/lldb/cmake/modules/LLDBStandalone.cmake
+++ b/lldb/cmake/modules/LLDBStandalone.cmake
@ -76,7 +76,7 @@ endif()

 # They are used as destination of target generators.
 set(LLVM_RUNTIME_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin)
-set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib)
+set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib${LLVM_LIBDIR_SUFFIX})
 if(WIN32 OR CYGWIN)
  # DLL platform -- put DLLs into bin.
  set(LLVM_SHLIB_OUTPUT_INTDIR ${LLVM_RUNTIME_OUTPUT_INTDIR})
@ -128,5 +128,5 @@ if(NOT DEFINED LLVM_COMMON_CMAKE_UTILS)
 endif()

 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
-set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)
-set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)
+set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX})
+set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX})
--- a/lldb/include/lldb/Host/Config.h.cmake
+++ b/lldb/include/lldb/Host/Config.h.cmake
@ -51,7 +51,7 @@

 #cmakedefine LLDB_PYTHON_HOME R"(${LLDB_PYTHON_HOME})"

-#define LLDB_INSTALL_LIBDIR_BASENAME "${LLDB_INSTALL_LIBDIR_BASENAME}"
+#define LLDB_LIBDIR_SUFFIX "${LLVM_LIBDIR_SUFFIX}"

 #cmakedefine LLDB_GLOBAL_INIT_DIRECTORY R"(${LLDB_GLOBAL_INIT_DIRECTORY})"

--- a/lldb/source/API/CMakeLists.txt
+++ b/lldb/source/API/CMakeLists.txt
@ -1,5 +1,3 @@
-include(ExtendPath)
-
 get_property(LLDB_ALL_PLUGINS GLOBAL PROPERTY LLDB_PLUGINS)

 if(LLDB_BUILD_FRAMEWORK)
@ -116,8 +114,7 @@ add_lldb_library(liblldb SHARED ${option_framework}
 # (LLVM_LINK_LLVM_DYLIB). Add an additional rpath $ORIGIN/../../../../lib so
 # that _lldb.so can be loaded from Python.
 if(LLDB_ENABLE_PYTHON AND (BUILD_SHARED_LIBS OR LLVM_LINK_LLVM_DYLIB) AND UNIX AND NOT APPLE)
-  extend_path(install_rpath "\$ORIGIN/../../../../" "${CMAKE_INSTALL_LIBDIR}")
-  set_property(TARGET liblldb APPEND PROPERTY INSTALL_RPATH "${install_rpath}")
+  set_property(TARGET liblldb APPEND PROPERTY INSTALL_RPATH "\$ORIGIN/../../../../lib${LLVM_LIBDIR_SUFFIX}")
 endif()

 if(Python3_RPATH)
--- a/lldb/source/Host/linux/HostInfoLinux.cpp
+++ b/lldb/source/Host/linux/HostInfoLinux.cpp
@ -175,7 +175,7 @@ bool HostInfoLinux::ComputeSupportExeDirectory(FileSpec &file_spec) {
 }

 bool HostInfoLinux::ComputeSystemPluginsDirectory(FileSpec &file_spec) {
-  FileSpec temp_file("/usr/" LLDB_INSTALL_LIBDIR_BASENAME "/lldb/plugins");
+  FileSpec temp_file("/usr/lib" LLDB_LIBDIR_SUFFIX "/lldb/plugins");
  FileSystem::Instance().Resolve(temp_file);
  file_spec.SetDirectory(temp_file.GetPath());
  return true;
--- a/lldb/source/Plugins/ExpressionParser/Clang/ClangHost.cpp
+++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangHost.cpp
@ -55,11 +55,11 @@ static bool DefaultComputeClangResourceDirectory(FileSpec &lldb_shlib_spec,
  static const llvm::StringRef kResourceDirSuffixes[] = {
      // LLVM.org's build of LLDB uses the clang resource directory placed
      // in $install_dir/lib{,64}/clang/$clang_version.
-      CLANG_INSTALL_LIBDIR_BASENAME "/clang/" CLANG_VERSION_STRING,
+      "lib" CLANG_LIBDIR_SUFFIX "/clang/" CLANG_VERSION_STRING,
      // swift-lldb uses the clang resource directory copied from swift, which
      // by default is placed in $install_dir/lib{,64}/lldb/clang. LLDB places
-      // it there, so we use LLDB_INSTALL_LIBDIR_BASENAME.
-      LLDB_INSTALL_LIBDIR_BASENAME "/lldb/clang",
+      // it there, so we use LLDB_LIBDIR_SUFFIX.
+      "lib" LLDB_LIBDIR_SUFFIX "/lldb/clang",
  };

  for (const auto &Suffix : kResourceDirSuffixes) {
--- a/lldb/tools/intel-features/CMakeLists.txt
+++ b/lldb/tools/intel-features/CMakeLists.txt
@ -30,4 +30,4 @@ add_lldb_library(lldbIntelFeatures SHARED
  )

 install(TARGETS lldbIntelFeatures
-  LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}")
+  LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX})
--- a/lldb/unittests/Expression/ClangParserTest.cpp
+++ b/lldb/unittests/Expression/ClangParserTest.cpp
@ -37,8 +37,7 @@ static std::string ComputeClangResourceDir(std::string lldb_shlib_path,
 TEST_F(ClangHostTest, ComputeClangResourceDirectory) {
 #if !defined(_WIN32)
  std::string path_to_liblldb = "/foo/bar/lib/";
-  std::string path_to_clang_dir =
-      "/foo/bar/" LLDB_INSTALL_LIBDIR_BASENAME "/clang/" CLANG_VERSION_STRING;
+  std::string path_to_clang_dir = "/foo/bar/lib" LLDB_LIBDIR_SUFFIX "/clang/" CLANG_VERSION_STRING;
 #else
  std::string path_to_liblldb = "C:\\foo\\bar\\lib";
  std::string path_to_clang_dir = "C:\\foo\\bar\\lib\\clang\\" CLANG_VERSION_STRING;
--- a/llvm/CMakeLists.txt
+++ b/llvm/CMakeLists.txt
@ -55,14 +55,6 @@ project(LLVM
  VERSION ${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR}.${LLVM_VERSION_PATCH}
  LANGUAGES C CXX ASM)

-if (NOT DEFINED CMAKE_INSTALL_LIBDIR AND DEFINED LLVM_LIBDIR_SUFFIX)
-  message(DEPRECATION
-    "\"LLVM_LIBDIR_SUFFIX\" is deprecated. "
-    "Please set \"CMAKE_INSTALL_LIBDIR\" directly instead.")
-  # Must go before `include(GNUInstallDirs)`.
-  set(CMAKE_INSTALL_LIBDIR "lib${LLVM_LIBDIR_SUFFIX}")
-endif()
-
 # Must go after project(..)
 include(GNUInstallDirs)

@ -345,6 +337,8 @@ if (CMAKE_BUILD_TYPE AND
  message(FATAL_ERROR "Invalid value for CMAKE_BUILD_TYPE: ${CMAKE_BUILD_TYPE}")
 endif()

+set(LLVM_LIBDIR_SUFFIX "" CACHE STRING "Define suffix of library directory name (32/64)" )
+
 # LLVM_INSTALL_PACKAGE_DIR needs to be declared prior to adding the tools
 # subdirectory in order to have the value available for llvm-config.
 include(GNUInstallPackageDir)
@ -365,7 +359,7 @@ mark_as_advanced(LLVM_EXAMPLES_INSTALL_DIR)

 # They are used as destination of target generators.
 set(LLVM_RUNTIME_OUTPUT_INTDIR ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin)
-set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib)
+set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib${LLVM_LIBDIR_SUFFIX})
 if(WIN32 OR CYGWIN)
  # DLL platform -- put DLLs into bin.
  set(LLVM_SHLIB_OUTPUT_INTDIR ${LLVM_RUNTIME_OUTPUT_INTDIR})
@ -922,8 +916,8 @@ configure_file(

 # They are not referenced. See set_output_directory().
 set( CMAKE_RUNTIME_OUTPUT_DIRECTORY ${LLVM_BINARY_DIR}/bin )
-set( CMAKE_LIBRARY_OUTPUT_DIRECTORY ${LLVM_BINARY_DIR}/lib )
-set( CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${LLVM_BINARY_DIR}/lib )
+set( CMAKE_LIBRARY_OUTPUT_DIRECTORY ${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX} )
+set( CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX} )

 if(LLVM_INCLUDE_TESTS)
  include(GetErrcMessages)
@ -981,7 +975,7 @@ if (NOT TENSORFLOW_AOT_PATH STREQUAL "")
  add_subdirectory(${TENSORFLOW_AOT_PATH}/xla_aot_runtime_src
    ${CMAKE_ARCHIVE_OUTPUT_DIRECTORY}/tf_runtime)
  install(TARGETS tf_xla_runtime EXPORT LLVMExports
-    ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}" COMPONENT tf_xla_runtime)
+    ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX} COMPONENT tf_xla_runtime)
  set_property(GLOBAL APPEND PROPERTY LLVM_EXPORTS tf_xla_runtime)
  # Once we add more modules, we should handle this more automatically.
  if (DEFINED LLVM_OVERRIDE_MODEL_HEADER_INLINERSIZEMODEL)
--- a/llvm/cmake/modules/AddLLVM.cmake
+++ b/llvm/cmake/modules/AddLLVM.cmake
@ -844,8 +844,8 @@ macro(add_llvm_library name)
      get_target_export_arg(${name} LLVM export_to_llvmexports ${umbrella})
      install(TARGETS ${name}
              ${export_to_llvmexports}
-              LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}" COMPONENT ${name}
-              ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}" COMPONENT ${name}
+              LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX} COMPONENT ${name}
+              ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX} COMPONENT ${name}
              RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}" COMPONENT ${name})

      if (NOT LLVM_ENABLE_IDE)
@ -1093,7 +1093,7 @@ function(process_llvm_pass_plugins)
          message(FATAL_ERROR "LLVM_INSTALL_PACKAGE_DIR must be defined and writable. GEN_CONFIG should only be passe when building LLVM proper.")
      endif()
      # LLVM_INSTALL_PACKAGE_DIR might be absolute, so don't reuse below.
-      set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib/cmake/llvm")
+      set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")
      file(WRITE
          "${llvm_cmake_builddir}/LLVMConfigExtensions.cmake"
          "set(LLVM_STATIC_EXTENSIONS ${LLVM_STATIC_EXTENSIONS})")
@ -2007,7 +2007,7 @@ function(llvm_install_library_symlink name dest type)
  set(full_name ${CMAKE_${type}_LIBRARY_PREFIX}${name}${CMAKE_${type}_LIBRARY_SUFFIX})
  set(full_dest ${CMAKE_${type}_LIBRARY_PREFIX}${dest}${CMAKE_${type}_LIBRARY_SUFFIX})

-  set(output_dir "${CMAKE_INSTALL_FULL_LIBDIR}")
+  set(output_dir lib${LLVM_LIBDIR_SUFFIX})
  if(WIN32 AND "${type}" STREQUAL "SHARED")
    set(output_dir "${CMAKE_INSTALL_BINDIR}")
  endif()
@ -2271,15 +2271,15 @@ function(llvm_setup_rpath name)

  if (APPLE)
    set(_install_name_dir INSTALL_NAME_DIR "@rpath")
-    set(_install_rpath "@loader_path/../${CMAKE_INSTALL_LIBDIR}" ${extra_libdir})
+    set(_install_rpath "@loader_path/../lib${LLVM_LIBDIR_SUFFIX}" ${extra_libdir})
  elseif(${CMAKE_SYSTEM_NAME} MATCHES "AIX" AND BUILD_SHARED_LIBS)
    # $ORIGIN is not interpreted at link time by aix ld.
    # Since BUILD_SHARED_LIBS is only recommended for use by developers,
    # hardcode the rpath to build/install lib dir first in this mode.
    # FIXME: update this when there is better solution.
-    set(_install_rpath "${LLVM_LIBRARY_OUTPUT_INTDIR}" "${CMAKE_INSTALL_FULL_LIBDIR}" ${extra_libdir})
+    set(_install_rpath "${LLVM_LIBRARY_OUTPUT_INTDIR}" "${CMAKE_INSTALL_PREFIX}/lib${LLVM_LIBDIR_SUFFIX}" ${extra_libdir})
  elseif(UNIX)
-    set(_install_rpath "\$ORIGIN/../${CMAKE_INSTALL_LIBDIR}" ${extra_libdir})
+    set(_install_rpath "\$ORIGIN/../lib${LLVM_LIBDIR_SUFFIX}" ${extra_libdir})
    if(${CMAKE_SYSTEM_NAME} MATCHES "(FreeBSD|DragonFly)")
      set_property(TARGET ${name} APPEND_STRING PROPERTY
                   LINK_FLAGS " -Wl,-z,origin ")
--- a/llvm/cmake/modules/AddOCaml.cmake
+++ b/llvm/cmake/modules/AddOCaml.cmake
@ -147,9 +147,9 @@ function(add_ocaml_library name)
  endforeach()

  if( APPLE )
-    set(ocaml_rpath "@executable_path/../../../${CMAKE_INSTALL_LIBDIR}")
+    set(ocaml_rpath "@executable_path/../../../lib${LLVM_LIBDIR_SUFFIX}")
  elseif( UNIX )
-    set(ocaml_rpath "\\$ORIGIN/../../../${CMAKE_INSTALL_LIBDIR}")
+    set(ocaml_rpath "\\$ORIGIN/../../../lib${LLVM_LIBDIR_SUFFIX}")
  endif()
  list(APPEND ocaml_flags "-ldopt" "-Wl,-rpath,${ocaml_rpath}")

--- a/llvm/cmake/modules/CMakeLists.txt
+++ b/llvm/cmake/modules/CMakeLists.txt
@ -3,7 +3,7 @@ include(LLVMDistributionSupport)
 include(FindPrefixFromConfig)

 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib/cmake/llvm")
+set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")

 # First for users who use an installed LLVM, create the LLVMExports.cmake file.
 set(LLVM_EXPORTS_FILE ${llvm_cmake_builddir}/LLVMExports.cmake)
@ -125,7 +125,7 @@ set(LLVM_CONFIG_INCLUDE_DIRS
  )
 list(REMOVE_DUPLICATES LLVM_CONFIG_INCLUDE_DIRS)

-extend_path(LLVM_CONFIG_LIBRARY_DIR "\${LLVM_INSTALL_PREFIX}" "${CMAKE_INSTALL_LIBDIR}")
+extend_path(LLVM_CONFIG_LIBRARY_DIR "\${LLVM_INSTALL_PREFIX}" "lib\${LLVM_LIBDIR_SUFFIX}")
 set(LLVM_CONFIG_LIBRARY_DIRS
  "${LLVM_CONFIG_LIBRARY_DIR}"
  # FIXME: Should there be other entries here?
--- a/llvm/cmake/modules/LLVMConfig.cmake.in
+++ b/llvm/cmake/modules/LLVMConfig.cmake.in
@ -104,6 +104,8 @@ set(LLVM_PLUGIN_EXT @LLVM_PLUGIN_EXT@)

 set(LLVM_ON_UNIX @LLVM_ON_UNIX@)

+set(LLVM_LIBDIR_SUFFIX @LLVM_LIBDIR_SUFFIX@)
+
 set(LLVM_INCLUDE_DIRS "@LLVM_CONFIG_INCLUDE_DIRS@")
 set(LLVM_LIBRARY_DIRS "@LLVM_CONFIG_LIBRARY_DIRS@")

@ -118,14 +120,6 @@ set(LLVM_APPEND_VC_REV "@LLVM_APPEND_VC_REV@")
 set(LLVM_MAIN_INCLUDE_DIR "@LLVM_CONFIG_MAIN_INCLUDE_DIR@")
 set(LLVM_LIBRARY_DIR "@LLVM_CONFIG_LIBRARY_DIR@")

-# Backwards compatibility for anything using the deprecated `LLVM_LIBDIR_SUFFIX`
-# downstream.
-if("{LLVM_LIBRARY_DIR}" MATCHES "lib([^/]*)$")
-  set(LLVM_LIBDIR_SUFFIX "${CMAKE_MATCH_0}")
-else()
-  set(LLVM_LIBDIR_SUFFIX "")
-endif()
-
 # This is a secondary one for generated files
 set(LLVM_INCLUDE_DIR "@LLVM_CONFIG_INCLUDE_DIR@")

--- a/llvm/docs/CMake.rst
+++ b/llvm/docs/CMake.rst
@ -247,6 +247,11 @@ description is in `LLVM-related variables`_ below.
  Control which runtimes are enabled. For example you may want to work on
  libc++ or libc++abi by specifying ``-DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi"``.

+**LLVM_LIBDIR_SUFFIX**:STRING
+  Extra suffix to append to the directory where libraries are to be
+  installed. On a 64-bit architecture, one could use ``-DLLVM_LIBDIR_SUFFIX=64``
+  to install libraries to ``/usr/lib64``.
+
 **LLVM_PARALLEL_{COMPILE,LINK}_JOBS**:STRING
  Building the llvm toolchain can use a lot of resources, particularly
  linking. These options, when you use the Ninja generator, allow you
@ -279,10 +284,6 @@ manual, or execute ``cmake --help-variable VARIABLE_NAME``.
  The path to install executables, relative to the *CMAKE_INSTALL_PREFIX*.
  Defaults to "bin".

-**CMAKE_INSTALL_LIBDIR**:PATH
-  The path to install libraries, relative to the *CMAKE_INSTALL_PREFIX*.
-  Defaults to "lib".
-
 **CMAKE_INSTALL_INCLUDEDIR**:PATH
  The path to install header files, relative to the *CMAKE_INSTALL_PREFIX*.
  Defaults to "include".
@ -830,21 +831,6 @@ things to go wrong.  They are also unstable across LLVM versions.
  Only matters if *LLVM_BUILD_EXAMPLES* is enabled.
  Defaults to "examples".

-Deprecated variables
-~~~~~~~~~~~~~~~~~~~~
-
-These will go away soon. Please try to avoid using them.
-
-**LLVM_LIBDIR_SUFFIX**:STRING
-
-  **Deprecated**: Use ``LLVM_LIBRARY_DIR`` or ``CMAKE_INSTALL_LIBDIR`` instead.
-  Only defined downstream for legacy consumers, not during the build of LLVM
-  itself.
-
-  Extra suffix to append to the directory where libraries are to be
-  installed. On a 64-bit architecture, one could use ``-DLLVM_LIBDIR_SUFFIX=64``
-  to install libraries to ``/usr/lib64``. See also ``CMAKE_INSTALL_LIBDIR``.
-
 CMake Caches
 ============

--- a/llvm/tools/llvm-config/BuildVariables.inc.in
+++ b/llvm/tools/llvm-config/BuildVariables.inc.in
@ -22,7 +22,7 @@
 #define LLVM_LDFLAGS "@LLVM_LDFLAGS@"
 #define LLVM_CXXFLAGS "@LLVM_CXXFLAGS@"
 #define LLVM_BUILDMODE "@LLVM_BUILDMODE@"
-#define LLVM_INSTALL_LIBDIR "@CMAKE_INSTALL_LIBDIR@"
+#define LLVM_LIBDIR_SUFFIX "@LLVM_LIBDIR_SUFFIX@"
 #define LLVM_INSTALL_INCLUDEDIR "@CMAKE_INSTALL_INCLUDEDIR@"
 #define LLVM_INSTALL_PACKAGE_DIR "@LLVM_INSTALL_PACKAGE_DIR@"
 #define LLVM_TARGETS_BUILT "@LLVM_TARGETS_BUILT@"
--- a/llvm/tools/llvm-config/llvm-config.cpp
+++ b/llvm/tools/llvm-config/llvm-config.cpp
@ -339,16 +339,18 @@ int main(int argc, char **argv) {
    switch (DevelopmentTreeLayout) {
    case CMakeStyle:
      ActiveBinDir = ActiveObjRoot + "/bin";
-      ActiveLibDir = ActiveObjRoot + "/lib";
+      ActiveLibDir = ActiveObjRoot + "/lib" + LLVM_LIBDIR_SUFFIX;
      ActiveCMakeDir = ActiveLibDir + "/cmake/llvm";
      break;
    case CMakeBuildModeStyle:
      // FIXME: Should we consider the build-mode-specific path as the prefix?
      ActivePrefix = ActiveObjRoot;
      ActiveBinDir = ActiveObjRoot + "/" + build_mode + "/bin";
-      ActiveLibDir = ActiveObjRoot + "/" + build_mode + "/lib";
+      ActiveLibDir =
+          ActiveObjRoot + "/" + build_mode + "/lib" + LLVM_LIBDIR_SUFFIX;
      // The CMake directory isn't separated by build mode.
-      ActiveCMakeDir = ActivePrefix + "/lib/cmake/llvm";
+      ActiveCMakeDir =
+          ActivePrefix + "/lib" + LLVM_LIBDIR_SUFFIX + "/cmake/llvm";
      break;
    }

@ -367,11 +369,7 @@ int main(int argc, char **argv) {
      sys::fs::make_absolute(ActivePrefix, Path);
      ActiveBinDir = std::string(Path.str());
    }
-    {
-      SmallString<256> Path(LLVM_INSTALL_LIBDIR);
-      sys::fs::make_absolute(ActivePrefix, Path);
-      ActiveLibDir = std::string(Path.str());
-    }
+    ActiveLibDir = ActivePrefix + "/lib" + LLVM_LIBDIR_SUFFIX;
    {
      SmallString<256> Path(LLVM_INSTALL_PACKAGE_DIR);
      sys::fs::make_absolute(ActivePrefix, Path);
--- a/llvm/tools/llvm-shlib/CMakeLists.txt
+++ b/llvm/tools/llvm-shlib/CMakeLists.txt
@ -88,7 +88,7 @@ if(LLVM_BUILD_LLVM_C_DYLIB AND NOT MSVC)

  set(LLVM_EXPORTED_SYMBOL_FILE ${LLVM_BINARY_DIR}/libllvm-c.exports)

-  set(LIB_DIR ${LLVM_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib)
+  set(LIB_DIR ${LLVM_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib${LLVM_LIBDIR_SUFFIX})
  set(LIB_NAME ${LIB_DIR}/${CMAKE_SHARED_LIBRARY_PREFIX}LLVM)
  set(LIB_PATH ${LIB_NAME}${CMAKE_SHARED_LIBRARY_SUFFIX})
  set(LIB_EXPORTS_PATH ${LIB_NAME}.exports)
--- a/llvm/utils/gn/secondary/clang/include/clang/Config/BUILD.gn
+++ b/llvm/utils/gn/secondary/clang/include/clang/Config/BUILD.gn
@ -20,6 +20,7 @@ write_cmake_config("Config") {
    "CLANG_DEFAULT_UNWINDLIB=",
    "CLANG_INSTALL_LIBDIR_BASENAME=lib",
    "CLANG_OPENMP_NVPTX_DEFAULT_ARCH=sm_35",
+    "CLANG_LIBDIR_SUFFIX=",
    "CLANG_RESOURCE_DIR=",
    "C_INCLUDE_DIRS=",
    "CLANG_CONFIG_FILE_SYSTEM_DIR=",
--- a/llvm/utils/gn/secondary/lldb/include/lldb/Host/BUILD.gn
+++ b/llvm/utils/gn/secondary/lldb/include/lldb/Host/BUILD.gn
@ -26,6 +26,8 @@ write_cmake_config("Config") {

    "LLDB_PYTHON_HOME=",

+    "LLVM_LIBDIR_SUFFIX=",
+
    "HAVE_LIBCOMPRESSION=",
  ]

--- a/llvm/utils/gn/secondary/llvm/tools/llvm-config/BUILD.gn
+++ b/llvm/utils/gn/secondary/llvm/tools/llvm-config/BUILD.gn
@ -71,7 +71,6 @@ write_cmake_config("BuildVariables.inc") {
  }

  values = [
-    "CMAKE_INSTALL_LIBDIR=lib",
    "CMAKE_INSTALL_INCLUDEDIR=include",
    "LLVM_SRC_ROOT=" + rebase_path("//llvm"),
    "LLVM_OBJ_ROOT=" + rebase_path(root_out_dir),
@ -82,6 +81,7 @@ write_cmake_config("BuildVariables.inc") {
    "LLVM_LDFLAGS=.",  # FIXME
    "LLVM_CXXFLAGS=.",  # FIXME
    "LLVM_BUILDMODE=$build_mode",
+    "LLVM_LIBDIR_SUFFIX=",
    "LLVM_TARGETS_BUILT=$llvm_targets_to_build_string",
    "LLVM_SYSTEM_LIBS=$system_libs",
    "LLVM_BUILD_SYSTEM=gn",
--- a/mlir/CMakeLists.txt
+++ b/mlir/CMakeLists.txt
@ -28,7 +28,7 @@ if(MLIR_STANDALONE_BUILD)
  endif()

  set(CMAKE_LIBRARY_OUTPUT_DIRECTORY
-    "${CMAKE_CURRENT_BINARY_DIR}/lib")
+    "${CMAKE_CURRENT_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}")
  set(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/bin")
 endif()

--- a/mlir/cmake/modules/AddMLIR.cmake
+++ b/mlir/cmake/modules/AddMLIR.cmake
@ -533,13 +533,13 @@ function(add_mlir_library_install name)
  install(TARGETS ${name}
    COMPONENT ${name}
    ${export_to_mlirtargets}
-    LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
-    ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+    LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX}
+    ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX}
    RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}"
    # Note that CMake will create a directory like:
    #   objects-${CMAKE_BUILD_TYPE}/obj.LibName
    # and put object files there.
-    OBJECTS DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+    OBJECTS DESTINATION lib${LLVM_LIBDIR_SUFFIX}
  )

  if (NOT LLVM_ENABLE_IDE)
--- a/mlir/cmake/modules/AddMLIRPython.cmake
+++ b/mlir/cmake/modules/AddMLIRPython.cmake
@ -408,12 +408,8 @@ function(mlir_python_setup_extension_rpath target)
    get_filename_component(_real_lib_dir "${LLVM_LIBRARY_OUTPUT_INTDIR}" REALPATH)
    set_property(TARGET ${target} APPEND PROPERTY
      BUILD_RPATH "${_real_lib_dir}")
-    if(NOT IS_ABSOLUTE "${CMAKE_INSTALL_LIBDIR}")
-      set(install_rpath "${_origin_prefix}/${ARG_RELATIVE_INSTALL_ROOT}/${CMAKE_INSTALL_LIBDIR}")
-	else()
-	  set(install_rpath "${CMAKE_INSTALL_LIBDIR}")
-	endif()
-    set_property(TARGET ${target} APPEND PROPERTY INSTALL_RPATH "${install_rpath}")
+    set_property(TARGET ${target} APPEND PROPERTY
+      INSTALL_RPATH "${_origin_prefix}/${ARG_RELATIVE_INSTALL_ROOT}/lib${LLVM_LIBDIR_SUFFIX}")
  endif()
 endfunction()

--- a/mlir/cmake/modules/CMakeLists.txt
+++ b/mlir/cmake/modules/CMakeLists.txt
@ -9,13 +9,13 @@ include(FindPrefixFromConfig)
 set(MLIR_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/mlir" CACHE STRING
  "Path for CMake subdirectory for Polly (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/polly')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(mlir_cmake_builddir "${CMAKE_BINARY_DIR}/lib/cmake/mlir")
+set(mlir_cmake_builddir "${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/mlir")

 # Keep this in sync with llvm/cmake/CMakeLists.txt!
 set(LLVM_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/llvm" CACHE STRING
  "Path for CMake subdirectory for LLVM (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/llvm')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib/cmake/llvm")
+set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")

 get_property(MLIR_EXPORTS GLOBAL PROPERTY MLIR_EXPORTS)
 export(TARGETS ${MLIR_EXPORTS} FILE ${mlir_cmake_builddir}/MLIRTargets.cmake)
--- a/mlir/test/CMakeLists.txt
+++ b/mlir/test/CMakeLists.txt
@ -8,7 +8,7 @@ endif()
 # Passed to lit.site.cfg.py.so that the out of tree Standalone dialect test
 # can find MLIR's CMake configuration
 set(MLIR_CMAKE_DIR
-  "${CMAKE_BINARY_DIR}/lib/cmake/mlir")
+  "${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/mlir")

 # Passed to lit.site.cfg.py.in to set up the path where to find the libraries
 # for linalg integration tests.
--- a/openmp/CMakeLists.txt
+++ b/openmp/CMakeLists.txt
@ -17,9 +17,6 @@ endif()
 # Must go below project(..)
 include(GNUInstallDirs)

-set(OPENMP_INSTALL_LIBDIR "${CMAKE_INSTALL_LIBDIR}" CACHE STRING
-  "lib installation directory, e.g. lib or lib64")
-
 if (OPENMP_STANDALONE_BUILD)
  # CMAKE_BUILD_TYPE was not set, default to Release.
  if (NOT CMAKE_BUILD_TYPE)
@ -29,6 +26,10 @@ if (OPENMP_STANDALONE_BUILD)
  # Group common settings.
  set(OPENMP_ENABLE_WERROR FALSE CACHE BOOL
    "Enable -Werror flags to turn warnings into errors for supporting compilers.")
+  set(OPENMP_LIBDIR_SUFFIX "" CACHE STRING
+    "Suffix of lib installation directory, e.g. 64 => lib64")
+  # Do not use OPENMP_LIBDIR_SUFFIX directly, use OPENMP_INSTALL_LIBDIR.
+  set(OPENMP_INSTALL_LIBDIR "lib${OPENMP_LIBDIR_SUFFIX}")

  # Group test settings.
  set(OPENMP_TEST_C_COMPILER ${CMAKE_C_COMPILER} CACHE STRING
@ -38,6 +39,8 @@ if (OPENMP_STANDALONE_BUILD)
  set(OPENMP_LLVM_TOOLS_DIR "" CACHE PATH "Path to LLVM tools for testing.")
 else()
  set(OPENMP_ENABLE_WERROR ${LLVM_ENABLE_WERROR})
+  # If building in tree, we honor the same install suffix LLVM uses.
+  set(OPENMP_INSTALL_LIBDIR "lib${LLVM_LIBDIR_SUFFIX}")

  if (NOT MSVC)
    set(OPENMP_TEST_C_COMPILER ${LLVM_RUNTIME_OUTPUT_INTDIR}/clang)
--- a/openmp/README.rst
+++ b/openmp/README.rst
@ -108,8 +108,8 @@ Options for all Libraries
 **OPENMP_ENABLE_WERROR** = ``OFF|ON``
  Treat warnings as errors and fail, if a compiler warning is triggered.

-**OPENMP_INSTALL_LIBDIR** = ``lib``
-  Name or path of the directory where libraries are to be installed.
+**OPENMP_LIBDIR_SUFFIX** = ``""``
+  Extra suffix to append to the directory where libraries are to be installed.

 **OPENMP_TEST_C_COMPILER** = ``${CMAKE_C_COMPILER}``
  Compiler to use for testing. Defaults to the compiler that was also used for
--- a/polly/cmake/CMakeLists.txt
+++ b/polly/cmake/CMakeLists.txt
@ -7,12 +7,12 @@ include(FindPrefixFromConfig)
 set(POLLY_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/polly" CACHE STRING
  "Path for CMake subdirectory for Polly (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/polly')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(polly_cmake_builddir "${POLLY_BINARY_DIR}/lib/cmake/polly")
+set(polly_cmake_builddir "${POLLY_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/polly")

 set(LLVM_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/llvm" CACHE STRING
  "Path for CMake subdirectory for LLVM (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/llvm')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib/cmake/llvm")
+set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")

 if (CMAKE_CONFIGURATION_TYPES)
  set(POLLY_EXPORTS_FILE_NAME "PollyExports-$<LOWER_CASE:$<CONFIG>>.cmake")
@ -93,7 +93,7 @@ unset(POLLY_EXPORTS)
 find_prefix_from_config(POLLY_CONFIG_CODE POLLY_INSTALL_PREFIX "${POLLY_INSTALL_PACKAGE_DIR}")
 extend_path(POLLY_CONFIG_LLVM_CMAKE_DIR "\${POLLY_INSTALL_PREFIX}" "${LLVM_INSTALL_PACKAGE_DIR}")
 extend_path(POLLY_CONFIG_CMAKE_DIR "\${POLLY_INSTALL_PREFIX}" "${POLLY_INSTALL_PACKAGE_DIR}")
-extend_path(POLLY_CONFIG_LIBRARY_DIRS "\${POLLY_INSTALL_PREFIX}" "${CMAKE_INSTALL_LIBDIR}")
+extend_path(POLLY_CONFIG_LIBRARY_DIRS "\${POLLY_INSTALL_PREFIX}" "lib${LLVM_LIBDIR_SUFFIX}")
 extend_path(base_includedir "\${POLLY_INSTALL_PREFIX}" "${CMAKE_INSTALL_INCLUDEDIR}")
 if (POLLY_BUNDLED_ISL)
  set(POLLY_CONFIG_INCLUDE_DIRS
--- a/polly/cmake/polly_macros.cmake
+++ b/polly/cmake/polly_macros.cmake
@ -44,8 +44,8 @@ macro(add_polly_library name)
  if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY OR ${name} STREQUAL "LLVMPolly")
    install(TARGETS ${name}
      EXPORT LLVMExports
-      LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
-      ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}")
+      LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX}
+      ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX})
  endif()
  set_property(GLOBAL APPEND PROPERTY LLVM_EXPORTS ${name})
 endmacro(add_polly_library)
--- a/polly/test/CMakeLists.txt
+++ b/polly/test/CMakeLists.txt
@ -46,7 +46,7 @@ endif ()

 set(LLVM_BINARY_DIR "${LLVM_BINARY_DIR}")
 set(LLVM_TOOLS_DIR "${LLVM_TOOLS_BINARY_DIR}")
-set(LLVM_LIBS_DIR "${LLVM_BINARY_DIR}/lib")
+set(LLVM_LIBS_DIR "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}")
 if (CMAKE_LIBRARY_OUTPUT_DIRECTORY)
  set(POLLY_LIB_DIR ${CMAKE_LIBRARY_OUTPUT_DIRECTORY})
 else()
--- a/pstl/CMakeLists.txt
+++ b/pstl/CMakeLists.txt
@ -88,10 +88,10 @@ install(TARGETS ParallelSTL
 install(EXPORT ParallelSTLTargets
        FILE ParallelSTLTargets.cmake
        NAMESPACE pstl::
-        DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/ParallelSTL")
+        DESTINATION lib/cmake/ParallelSTL)
 install(FILES "${CMAKE_CURRENT_BINARY_DIR}/ParallelSTLConfig.cmake"
              "${CMAKE_CURRENT_BINARY_DIR}/ParallelSTLConfigVersion.cmake"
-        DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/ParallelSTL")
+        DESTINATION lib/cmake/ParallelSTL)
 install(DIRECTORY include/
        DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
        PATTERN "*.in" EXCLUDE)
--- a/third-party/benchmark/src/CMakeLists.txt
+++ b/third-party/benchmark/src/CMakeLists.txt
@ -79,7 +79,7 @@ include(CMakePackageConfigHelpers)
 configure_package_config_file (
  ${PROJECT_SOURCE_DIR}/cmake/Config.cmake.in
  ${project_config}
-  INSTALL_DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME}"
+  INSTALL_DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME}
  NO_SET_AND_CHECK_MACRO
  NO_CHECK_REQUIRED_COMPONENTS_MACRO
 )
@ -100,8 +100,8 @@ if (BENCHMARK_ENABLE_INSTALL)
  install(
    TARGETS ${targets_to_export}
    EXPORT ${targets_export_name}
-    ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}"
-    LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+    ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
+    LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
    RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
    INCLUDES DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})

--- a/utils/bazel/llvm-project-overlay/clang/include/clang/Config/config.h
+++ b/utils/bazel/llvm-project-overlay/clang/include/clang/Config/config.h
@ -67,8 +67,8 @@
 /* Default architecture for SystemZ. */
 #define CLANG_SYSTEMZ_DEFAULT_ARCH "z10"

-/* Multilib basename for libdir. */
-#define CLANG_INSTALL_LIBDIR_BASENAME "lib"
+/* Multilib suffix for libdir. */
+#define CLANG_LIBDIR_SUFFIX ""

 /* Relative directory for resource files */
 #define CLANG_RESOURCE_DIR ""