diff --git a/clang-tools-extra/CMakeLists.txt b/clang-tools-extra/CMakeLists.txt
--- a/clang-tools-extra/CMakeLists.txt
+++ b/clang-tools-extra/CMakeLists.txt
@@ -1,4 +1,5 @@
 include(CMakeDependentOption)
+include(GNUInstallDirs)
 
 option(CLANG_TIDY_ENABLE_STATIC_ANALYZER
   "Include static analyzer checks in clang-tidy" ON)
diff --git a/clang-tools-extra/clang-doc/tool/CMakeLists.txt b/clang-tools-extra/clang-doc/tool/CMakeLists.txt
--- a/clang-tools-extra/clang-doc/tool/CMakeLists.txt
+++ b/clang-tools-extra/clang-doc/tool/CMakeLists.txt
@@ -19,9 +19,9 @@
   )
 
 install(FILES ../assets/clang-doc-default-stylesheet.css
-  DESTINATION share/clang
+  DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
   COMPONENT clang-doc)
 
 install(FILES ../assets/index.js
-  DESTINATION share/clang
+  DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
   COMPONENT clang-doc)
diff --git a/clang-tools-extra/clang-include-fixer/find-all-symbols/tool/CMakeLists.txt b/clang-tools-extra/clang-include-fixer/find-all-symbols/tool/CMakeLists.txt
--- a/clang-tools-extra/clang-include-fixer/find-all-symbols/tool/CMakeLists.txt
+++ b/clang-tools-extra/clang-include-fixer/find-all-symbols/tool/CMakeLists.txt
@@ -20,5 +20,5 @@
   )
 
 install(PROGRAMS run-find-all-symbols.py
-  DESTINATION share/clang
+  DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
   COMPONENT find-all-symbols)
diff --git a/clang-tools-extra/clang-include-fixer/tool/CMakeLists.txt b/clang-tools-extra/clang-include-fixer/tool/CMakeLists.txt
--- a/clang-tools-extra/clang-include-fixer/tool/CMakeLists.txt
+++ b/clang-tools-extra/clang-include-fixer/tool/CMakeLists.txt
@@ -21,8 +21,8 @@
   )
 
 install(PROGRAMS clang-include-fixer.el
-  DESTINATION share/clang
+  DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
   COMPONENT clang-include-fixer)
 install(PROGRAMS clang-include-fixer.py
-  DESTINATION share/clang
+  DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
   COMPONENT clang-include-fixer)
diff --git a/clang-tools-extra/clang-tidy/CMakeLists.txt b/clang-tools-extra/clang-tidy/CMakeLists.txt
--- a/clang-tools-extra/clang-tidy/CMakeLists.txt
+++ b/clang-tools-extra/clang-tidy/CMakeLists.txt
@@ -113,7 +113,7 @@
 
 if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
   install(DIRECTORY .
-    DESTINATION include/clang-tidy
+    DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/clang-tidy"
     COMPONENT clang-tidy-headers
     FILES_MATCHING
     PATTERN "*.h"
diff --git a/clang-tools-extra/clang-tidy/tool/CMakeLists.txt b/clang-tools-extra/clang-tidy/tool/CMakeLists.txt
--- a/clang-tools-extra/clang-tidy/tool/CMakeLists.txt
+++ b/clang-tools-extra/clang-tidy/tool/CMakeLists.txt
@@ -52,9 +52,9 @@
 
 
 install(PROGRAMS clang-tidy-diff.py
-  DESTINATION share/clang
+  DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
   COMPONENT clang-tidy)
 install(PROGRAMS run-clang-tidy.py
-  DESTINATION bin
+  DESTINATION "${CMAKE_INSTALL_BINDIR}"
   COMPONENT clang-tidy
   RENAME run-clang-tidy)
diff --git a/clang-tools-extra/modularize/CMakeLists.txt b/clang-tools-extra/modularize/CMakeLists.txt
--- a/clang-tools-extra/modularize/CMakeLists.txt
+++ b/clang-tools-extra/modularize/CMakeLists.txt
@@ -23,5 +23,5 @@
   )
 
 install(TARGETS modularize
-        RUNTIME DESTINATION bin
+        RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}"
         COMPONENT clang-extras)
diff --git a/clang/CMakeLists.txt b/clang/CMakeLists.txt
--- a/clang/CMakeLists.txt
+++ b/clang/CMakeLists.txt
@@ -1,5 +1,7 @@
 cmake_minimum_required(VERSION 3.13.4)
 
+include(GNUInstallDirs)
+
 # If we are not building as a part of LLVM, build Clang as an
 # standalone project, using LLVM as an external library:
 if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
@@ -424,7 +426,7 @@
 
 if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
   install(DIRECTORY include/clang include/clang-c
-    DESTINATION include
+    DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
     COMPONENT clang-headers
     FILES_MATCHING
     PATTERN "*.def"
@@ -433,7 +435,7 @@
     )
 
   install(DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/include/clang
-    DESTINATION include
+    DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
     COMPONENT clang-headers
     FILES_MATCHING
     PATTERN "CMakeFiles" EXCLUDE
@@ -453,7 +455,7 @@
 
   add_custom_target(bash-autocomplete DEPENDS utils/bash-autocomplete.sh)
   install(PROGRAMS utils/bash-autocomplete.sh
-          DESTINATION share/clang
+          DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
           COMPONENT bash-autocomplete)
   if(NOT LLVM_ENABLE_IDE)
     add_llvm_install_targets(install-bash-autocomplete
diff --git a/clang/cmake/modules/AddClang.cmake b/clang/cmake/modules/AddClang.cmake
--- a/clang/cmake/modules/AddClang.cmake
+++ b/clang/cmake/modules/AddClang.cmake
@@ -1,3 +1,4 @@
+include(GNUInstallDirs)
 include(LLVMDistributionSupport)
 
 function(clang_tablegen)
@@ -120,7 +121,7 @@
           ${export_to_clangtargets}
           LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX}
           ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX}
-          RUNTIME DESTINATION bin)
+          RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}")
 
         if (NOT LLVM_ENABLE_IDE)
           add_llvm_install_targets(install-${lib}
@@ -159,7 +160,7 @@
     get_target_export_arg(${name} Clang export_to_clangtargets)
     install(TARGETS ${name}
       ${export_to_clangtargets}
-      RUNTIME DESTINATION bin
+      RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}"
       COMPONENT ${name})
 
     if(NOT LLVM_ENABLE_IDE)
diff --git a/clang/tools/c-index-test/CMakeLists.txt b/clang/tools/c-index-test/CMakeLists.txt
--- a/clang/tools/c-index-test/CMakeLists.txt
+++ b/clang/tools/c-index-test/CMakeLists.txt
@@ -49,7 +49,7 @@
     set_property(TARGET c-index-test APPEND PROPERTY INSTALL_RPATH
        "@executable_path/../../lib")
   else()
-    set(INSTALL_DESTINATION bin)
+    set(INSTALL_DESTINATION "${CMAKE_INSTALL_BINDIR}")
   endif()
 
   install(TARGETS c-index-test
diff --git a/clang/tools/clang-format/CMakeLists.txt b/clang/tools/clang-format/CMakeLists.txt
--- a/clang/tools/clang-format/CMakeLists.txt
+++ b/clang/tools/clang-format/CMakeLists.txt
@@ -21,20 +21,20 @@
 endif()
 
 install(PROGRAMS clang-format-bbedit.applescript
-  DESTINATION share/clang
+  DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
   COMPONENT clang-format)
 install(PROGRAMS clang-format-diff.py
-  DESTINATION share/clang
+  DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
   COMPONENT clang-format)
 install(PROGRAMS clang-format-sublime.py
-  DESTINATION share/clang
+  DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
   COMPONENT clang-format)
 install(PROGRAMS clang-format.el
-  DESTINATION share/clang
+  DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
   COMPONENT clang-format)
 install(PROGRAMS clang-format.py
-  DESTINATION share/clang
+  DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
   COMPONENT clang-format)
 install(PROGRAMS git-clang-format
-  DESTINATION bin
+  DESTINATION "${CMAKE_INSTALL_BINDIR}"
   COMPONENT clang-format)
diff --git a/clang/tools/clang-nvlink-wrapper/CMakeLists.txt b/clang/tools/clang-nvlink-wrapper/CMakeLists.txt
--- a/clang/tools/clang-nvlink-wrapper/CMakeLists.txt
+++ b/clang/tools/clang-nvlink-wrapper/CMakeLists.txt
@@ -22,4 +22,4 @@
   ${CLANG_NVLINK_WRAPPER_LIB_DEPS}
   )
 
-install(TARGETS clang-nvlink-wrapper RUNTIME DESTINATION bin)
+install(TARGETS clang-nvlink-wrapper RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}")
diff --git a/clang/tools/clang-rename/CMakeLists.txt b/clang/tools/clang-rename/CMakeLists.txt
--- a/clang/tools/clang-rename/CMakeLists.txt
+++ b/clang/tools/clang-rename/CMakeLists.txt
@@ -19,8 +19,8 @@
   )
 
 install(PROGRAMS clang-rename.py
-  DESTINATION share/clang
+  DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
   COMPONENT clang-rename)
 install(PROGRAMS clang-rename.el
-  DESTINATION share/clang
+  DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
   COMPONENT clang-rename)
diff --git a/clang/tools/libclang/CMakeLists.txt b/clang/tools/libclang/CMakeLists.txt
--- a/clang/tools/libclang/CMakeLists.txt
+++ b/clang/tools/libclang/CMakeLists.txt
@@ -186,7 +186,7 @@
 if(INTERNAL_INSTALL_PREFIX)
   set(LIBCLANG_HEADERS_INSTALL_DESTINATION "${INTERNAL_INSTALL_PREFIX}/include")
 else()
-  set(LIBCLANG_HEADERS_INSTALL_DESTINATION include)
+  set(LIBCLANG_HEADERS_INSTALL_DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}")
 endif()
 
 install(DIRECTORY ../../include/clang-c
diff --git a/clang/tools/scan-build-py/CMakeLists.txt b/clang/tools/scan-build-py/CMakeLists.txt
--- a/clang/tools/scan-build-py/CMakeLists.txt
+++ b/clang/tools/scan-build-py/CMakeLists.txt
@@ -43,7 +43,7 @@
                          ${CMAKE_BINARY_DIR}/bin/scan-build-py
                        DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/bin/scan-build)
     install (PROGRAMS "bin/scan-build"
-             DESTINATION bin
+             DESTINATION "${CMAKE_INSTALL_BINDIR}"
              RENAME scan-build-py
              COMPONENT scan-build-py)
     list(APPEND Depends ${CMAKE_BINARY_DIR}/bin/scan-build-py)
@@ -56,7 +56,7 @@
                          ${CMAKE_BINARY_DIR}/bin/
                        DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/bin/${BinFile})
     install(PROGRAMS bin/${BinFile}
-            DESTINATION bin
+            DESTINATION "${CMAKE_INSTALL_BINDIR}"
             COMPONENT scan-build-py)
     list(APPEND Depends ${CMAKE_BINARY_DIR}/bin/${BinFile})
   endif()
@@ -72,7 +72,7 @@
                      DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/libexec/${lib})
   list(APPEND Depends ${CMAKE_BINARY_DIR}/libexec/${lib})
   install(PROGRAMS libexec/${lib}
-          DESTINATION libexec
+          DESTINATION "${CMAKE_INSTALL_LIBEXECDIR}"
           COMPONENT scan-build-py)
 endforeach()
 
diff --git a/clang/tools/scan-build/CMakeLists.txt b/clang/tools/scan-build/CMakeLists.txt
--- a/clang/tools/scan-build/CMakeLists.txt
+++ b/clang/tools/scan-build/CMakeLists.txt
@@ -47,7 +47,7 @@
                        DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/bin/${BinFile})
     list(APPEND Depends ${CMAKE_BINARY_DIR}/bin/${BinFile})
     install(PROGRAMS bin/${BinFile}
-            DESTINATION bin
+            DESTINATION "${CMAKE_INSTALL_BINDIR}"
             COMPONENT scan-build)
   endforeach()
 
@@ -61,7 +61,7 @@
                        DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/libexec/${LibexecFile})
     list(APPEND Depends ${CMAKE_BINARY_DIR}/libexec/${LibexecFile})
     install(PROGRAMS libexec/${LibexecFile}
-            DESTINATION libexec
+            DESTINATION "${CMAKE_INSTALL_LIBEXECDIR}"
             COMPONENT scan-build)
   endforeach()
 
@@ -89,7 +89,7 @@
                        DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/share/scan-build/${ShareFile})
     list(APPEND Depends ${CMAKE_BINARY_DIR}/share/scan-build/${ShareFile})
     install(FILES share/scan-build/${ShareFile}
-            DESTINATION share/scan-build
+            DESTINATION "${CMAKE_INSTALL_DATADIR}/scan-build"
             COMPONENT scan-build)
   endforeach()
 
diff --git a/clang/tools/scan-view/CMakeLists.txt b/clang/tools/scan-view/CMakeLists.txt
--- a/clang/tools/scan-view/CMakeLists.txt
+++ b/clang/tools/scan-view/CMakeLists.txt
@@ -20,7 +20,7 @@
                        DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/bin/${BinFile})
     list(APPEND Depends ${CMAKE_BINARY_DIR}/bin/${BinFile})
     install(PROGRAMS bin/${BinFile}
-            DESTINATION bin
+            DESTINATION "${CMAKE_INSTALL_BINDIR}"
             COMPONENT scan-view)
   endforeach()
 
@@ -34,7 +34,7 @@
                        DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/share/${ShareFile})
     list(APPEND Depends ${CMAKE_BINARY_DIR}/share/scan-view/${ShareFile})
     install(FILES share/${ShareFile}
-            DESTINATION share/scan-view
+            DESTINATION "${CMAKE_INSTALL_DATADIR}/scan-view"
             COMPONENT scan-view)
   endforeach()
 
diff --git a/clang/utils/hmaptool/CMakeLists.txt b/clang/utils/hmaptool/CMakeLists.txt
--- a/clang/utils/hmaptool/CMakeLists.txt
+++ b/clang/utils/hmaptool/CMakeLists.txt
@@ -10,7 +10,7 @@
 
 list(APPEND Depends ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin/${CLANG_HMAPTOOL})
 install(PROGRAMS ${CLANG_HMAPTOOL}
-        DESTINATION bin
+        DESTINATION "${CMAKE_INSTALL_BINDIR}"
         COMPONENT hmaptool)
 
 add_custom_target(hmaptool ALL DEPENDS ${Depends})
diff --git a/compiler-rt/cmake/base-config-ix.cmake b/compiler-rt/cmake/base-config-ix.cmake
--- a/compiler-rt/cmake/base-config-ix.cmake
+++ b/compiler-rt/cmake/base-config-ix.cmake
@@ -108,13 +108,13 @@
   set(COMPILER_RT_INSTALL_LIBRARY_DIR "${default_install_path}" CACHE PATH
     "Path where built compiler-rt libraries should be installed.")
 endif()
-extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" bin)
+extend_path(default_install_path "${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 "${COMPILER_RT_INSTALL_PATH}" include)
+extend_path(default_install_path "${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 "${COMPILER_RT_INSTALL_PATH}" share)
+extend_path(default_install_path "${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.")
 
diff --git a/libc/CMakeLists.txt b/libc/CMakeLists.txt
--- a/libc/CMakeLists.txt
+++ b/libc/CMakeLists.txt
@@ -1,5 +1,7 @@
 cmake_minimum_required(VERSION 3.13.4)
 
+include(GNUInstallDirs)
+
 # Use old version of target_sources command which converts the source
 # file paths to full paths.
 cmake_policy(SET CMP0076 OLD)
diff --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt
--- a/libcxx/CMakeLists.txt
+++ b/libcxx/CMakeLists.txt
@@ -10,6 +10,8 @@
 #===============================================================================
 cmake_minimum_required(VERSION 3.13.4)
 
+include(GNUInstallDirs)
+
 set(LLVM_COMMON_CMAKE_UTILS "${CMAKE_CURRENT_SOURCE_DIR}/../cmake")
 
 # Add path for custom modules
@@ -417,11 +419,11 @@
   set(LIBCXX_GENERATED_INCLUDE_TARGET_DIR "${LLVM_BINARY_DIR}/include/${LLVM_DEFAULT_TARGET_TRIPLE}/c++/v1")
   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_RUNTIME_DIR bin CACHE PATH
+  set(LIBCXX_INSTALL_RUNTIME_DIR "${CMAKE_INSTALL_BINDIR}" CACHE PATH
       "Path where built libc++ runtime libraries should be installed.")
-  set(LIBCXX_INSTALL_INCLUDE_DIR "include/c++/v1" CACHE PATH
+  set(LIBCXX_INSTALL_INCLUDE_DIR "${CMAKE_INSTALL_INCLUDEDIR}/c++/v1" CACHE PATH
       "Path where target-agnostic libc++ headers should be installed.")
-  set(LIBCXX_INSTALL_INCLUDE_TARGET_DIR "include/${LLVM_DEFAULT_TARGET_TRIPLE}/c++/v1" CACHE PATH
+  set(LIBCXX_INSTALL_INCLUDE_TARGET_DIR "${CMAKE_INSTALL_INCLUDEDIR}/${LLVM_DEFAULT_TARGET_TRIPLE}/c++/v1" CACHE PATH
       "Path where target-specific libc++ headers should be installed.")
   if(LIBCXX_LIBDIR_SUBDIR)
     string(APPEND LIBCXX_LIBRARY_DIR /${LIBCXX_LIBDIR_SUBDIR})
@@ -433,9 +435,9 @@
   set(LIBCXX_GENERATED_INCLUDE_TARGET_DIR "${LIBCXX_GENERATED_INCLUDE_DIR}")
   set(LIBCXX_INSTALL_LIBRARY_DIR lib${LIBCXX_LIBDIR_SUFFIX} CACHE PATH
       "Path where built libc++ libraries should be installed.")
-  set(LIBCXX_INSTALL_RUNTIME_DIR bin CACHE PATH
+  set(LIBCXX_INSTALL_RUNTIME_DIR "${CMAKE_INSTALL_BINDIR}/c++/v1" CACHE PATH
       "Path where built libc++ runtime libraries should be installed.")
-  set(LIBCXX_INSTALL_INCLUDE_DIR "include/c++/v1" CACHE PATH
+  set(LIBCXX_INSTALL_INCLUDE_DIR "${CMAKE_INSTALL_INCLUDEDIR}/c++/v1" CACHE PATH
       "Path where target-agnostic libc++ headers should be installed.")
   set(LIBCXX_INSTALL_INCLUDE_TARGET_DIR "${LIBCXX_INSTALL_INCLUDE_DIR}" CACHE PATH
       "Path where target-specific libc++ headers should be installed.")
@@ -445,9 +447,9 @@
   set(LIBCXX_GENERATED_INCLUDE_TARGET_DIR "${LIBCXX_GENERATED_INCLUDE_DIR}")
   set(LIBCXX_INSTALL_LIBRARY_DIR lib${LIBCXX_LIBDIR_SUFFIX} CACHE PATH
       "Path where built libc++ libraries should be installed.")
-  set(LIBCXX_INSTALL_RUNTIME_DIR bin CACHE PATH
+  set(LIBCXX_INSTALL_RUNTIME_DIR "${CMAKE_INSTALL_BINDIR}" CACHE PATH
       "Path where built libc++ runtime libraries should be installed.")
-  set(LIBCXX_INSTALL_INCLUDE_DIR "include/c++/v1" CACHE PATH
+  set(LIBCXX_INSTALL_INCLUDE_DIR "${CMAKE_INSTALL_INCLUDEDIR}/c++/v1" CACHE PATH
       "Path where target-agnostic libc++ headers should be installed.")
   set(LIBCXX_INSTALL_INCLUDE_TARGET_DIR "${LIBCXX_INSTALL_INCLUDE_DIR}" CACHE PATH
       "Path where target-specific libc++ headers should be installed.")
diff --git a/libcxx/cmake/Modules/HandleLibCXXABI.cmake b/libcxx/cmake/Modules/HandleLibCXXABI.cmake
--- a/libcxx/cmake/Modules/HandleLibCXXABI.cmake
+++ b/libcxx/cmake/Modules/HandleLibCXXABI.cmake
@@ -1,8 +1,9 @@
-
 #===============================================================================
 # Add an ABI library if appropriate
 #===============================================================================
 
+include(GNUInstallDirs)
+
 #
 # _setup_abi: Set up the build to use an ABI library
 #
@@ -63,7 +64,7 @@
 
         if (LIBCXX_INSTALL_HEADERS)
           install(FILES "${LIBCXX_BINARY_INCLUDE_DIR}/${fpath}"
-            DESTINATION include/c++/v1/${dstdir}
+            DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/c++/v1/${dstdir}"
             COMPONENT cxx-headers
             PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
             )
diff --git a/libcxxabi/CMakeLists.txt b/libcxxabi/CMakeLists.txt
--- a/libcxxabi/CMakeLists.txt
+++ b/libcxxabi/CMakeLists.txt
@@ -10,6 +10,8 @@
 
 cmake_minimum_required(VERSION 3.13.4)
 
+include(GNUInstallDirs)
+
 set(LLVM_COMMON_CMAKE_UTILS "${CMAKE_CURRENT_SOURCE_DIR}/../cmake")
 
 # Add path for custom modules
@@ -215,7 +217,7 @@
   set(LIBCXXABI_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
   set(LIBCXXABI_INSTALL_LIBRARY_DIR lib${LLVM_LIBDIR_SUFFIX}/${LLVM_DEFAULT_TARGET_TRIPLE} CACHE PATH
       "Path where built libc++abi libraries should be installed.")
-  set(LIBCXXABI_INSTALL_RUNTIME_DIR bin CACHE PATH
+  set(LIBCXXABI_INSTALL_RUNTIME_DIR "${CMAKE_INSTALL_BINDIR}" CACHE PATH
       "Path where built libc++abi runtime libraries should be installed.")
   if(LIBCXX_LIBDIR_SUBDIR)
     string(APPEND LIBCXXABI_LIBRARY_DIR /${LIBCXXABI_LIBDIR_SUBDIR})
@@ -226,14 +228,14 @@
   set(LIBCXXABI_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR})
   set(LIBCXXABI_INSTALL_LIBRARY_DIR lib${LIBCXXABI_LIBDIR_SUFFIX} CACHE PATH
       "Path where built libc++abi libraries should be installed.")
-  set(LIBCXXABI_INSTALL_RUNTIME_DIR bin CACHE PATH
+  set(LIBCXXABI_INSTALL_RUNTIME_DIR "${CMAKE_INSTALL_BINDIR}" CACHE PATH
       "Path where built libc++abi runtime libraries should be installed.")
 else()
   set(LIBCXXABI_HEADER_DIR ${CMAKE_BINARY_DIR})
   set(LIBCXXABI_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LIBCXXABI_LIBDIR_SUFFIX})
   set(LIBCXXABI_INSTALL_LIBRARY_DIR lib${LIBCXXABI_LIBDIR_SUFFIX} CACHE PATH
       "Path where built libc++abi libraries should be installed.")
-  set(LIBCXXABI_INSTALL_RUNTIME_DIR bin CACHE PATH
+  set(LIBCXXABI_INSTALL_RUNTIME_DIR "${CMAKE_INSTALL_BINDIR}" CACHE PATH
       "Path where built libc++abi runtime libraries should be installed.")
 endif()
 
diff --git a/libunwind/CMakeLists.txt b/libunwind/CMakeLists.txt
--- a/libunwind/CMakeLists.txt
+++ b/libunwind/CMakeLists.txt
@@ -8,6 +8,8 @@
 
 cmake_minimum_required(VERSION 3.13.4)
 
+include(GNUInstallDirs)
+
 set(LLVM_COMMON_CMAKE_UTILS "${CMAKE_CURRENT_SOURCE_DIR}/../cmake")
 
 # Add path for custom modules
@@ -155,9 +157,9 @@
       "Path where built libunwind libraries should be installed.")
 endif()
 
-set(LIBUNWIND_INSTALL_INCLUDE_DIR include CACHE PATH
+set(LIBUNWIND_INSTALL_INCLUDE_DIR "${CMAKE_INSTALL_INCLUDEDIR}" CACHE PATH
     "Path where built libunwind headers should be installed.")
-set(LIBUNWIND_INSTALL_RUNTIME_DIR bin CACHE PATH
+set(LIBUNWIND_INSTALL_RUNTIME_DIR "${CMAKE_INSTALL_BINDIR}" CACHE PATH
     "Path where built libunwind runtime libraries should be installed.")
 
 set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${LIBUNWIND_LIBRARY_DIR})
diff --git a/llvm/cmake/modules/LLVMInstallSymlink.cmake b/llvm/cmake/modules/LLVMInstallSymlink.cmake
--- a/llvm/cmake/modules/LLVMInstallSymlink.cmake
+++ b/llvm/cmake/modules/LLVMInstallSymlink.cmake
@@ -6,7 +6,8 @@
 
 function(install_symlink name target outdir)
   set(DESTDIR $ENV{DESTDIR})
-  set(bindir "${DESTDIR}${CMAKE_INSTALL_PREFIX}/${outdir}")
+  GNUInstallDirs_get_absolute_install_dir(bindir "${outdir}" BINDIR)
+  set(bindir "${DESTDIR}${bindir}")
 
   message(STATUS "Creating ${name}")
 
diff --git a/mlir/CMakeLists.txt b/mlir/CMakeLists.txt
--- a/mlir/CMakeLists.txt
+++ b/mlir/CMakeLists.txt
@@ -1,5 +1,7 @@
 # MLIR project.
 
+include(GNUInstallDirs)
+
 # Check if MLIR is built as a standalone project.
 if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
   project(mlir)
@@ -173,7 +175,7 @@
 
 if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
   install(DIRECTORY include/mlir include/mlir-c
-    DESTINATION include
+    DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
     COMPONENT mlir-headers
     FILES_MATCHING
     PATTERN "*.def"
@@ -184,7 +186,7 @@
     )
 
   install(DIRECTORY ${MLIR_INCLUDE_DIR}/mlir ${MLIR_INCLUDE_DIR}/mlir-c
-    DESTINATION include
+    DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
     COMPONENT mlir-headers
     FILES_MATCHING
     PATTERN "*.def"
diff --git a/mlir/cmake/modules/AddMLIR.cmake b/mlir/cmake/modules/AddMLIR.cmake
--- a/mlir/cmake/modules/AddMLIR.cmake
+++ b/mlir/cmake/modules/AddMLIR.cmake
@@ -1,3 +1,4 @@
+include(GNUInstallDirs)
 include(LLVMDistributionSupport)
 
 function(mlir_tablegen ofn)
@@ -371,7 +372,7 @@
     ${export_to_mlirtargets}
     LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX}
     ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX}
-    RUNTIME DESTINATION bin
+    RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}"
     # Note that CMake will create a directory like:
     #   objects-${CMAKE_BUILD_TYPE}/obj.LibName
     # and put object files there.
diff --git a/openmp/CMakeLists.txt b/openmp/CMakeLists.txt
--- a/openmp/CMakeLists.txt
+++ b/openmp/CMakeLists.txt
@@ -1,5 +1,7 @@
 cmake_minimum_required(VERSION 3.13.4)
 
+include(GNUInstallDirs)
+
 # Add cmake directory to search for custom cmake functions.
 set(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake ${CMAKE_MODULE_PATH})
 
diff --git a/openmp/libompd/src/CMakeLists.txt b/openmp/libompd/src/CMakeLists.txt
--- a/openmp/libompd/src/CMakeLists.txt
+++ b/openmp/libompd/src/CMakeLists.txt
@@ -47,4 +47,4 @@
 INSTALL( TARGETS ompd
         LIBRARY DESTINATION ${OPENMP_INSTALL_LIBDIR}
         ARCHIVE DESTINATION ${OPENMP_INSTALL_LIBDIR}
-        RUNTIME DESTINATION bin )
+        RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}" )
diff --git a/openmp/runtime/src/CMakeLists.txt b/openmp/runtime/src/CMakeLists.txt
--- a/openmp/runtime/src/CMakeLists.txt
+++ b/openmp/runtime/src/CMakeLists.txt
@@ -346,19 +346,19 @@
 # We want to install libomp in DESTDIR/CMAKE_INSTALL_PREFIX/lib
 # We want to install headers in DESTDIR/CMAKE_INSTALL_PREFIX/include
 if(${OPENMP_STANDALONE_BUILD})
-  set(LIBOMP_HEADERS_INSTALL_PATH include)
+  set(LIBOMP_HEADERS_INSTALL_PATH "${CMAKE_INSTALL_INCLUDEDIR}")
 else()
   string(REGEX MATCH "[0-9]+\\.[0-9]+(\\.[0-9]+)?" CLANG_VERSION ${PACKAGE_VERSION})
   set(LIBOMP_HEADERS_INSTALL_PATH "${OPENMP_INSTALL_LIBDIR}/clang/${CLANG_VERSION}/include")
 endif()
 if(WIN32)
-  install(TARGETS omp RUNTIME DESTINATION bin)
+  install(TARGETS omp RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}")
   install(TARGETS ${LIBOMP_IMP_LIB_TARGET} ARCHIVE DESTINATION "${OPENMP_INSTALL_LIBDIR}")
   # Create aliases (regular copies) of the library for backwards compatibility
   set(LIBOMP_ALIASES "libiomp5md")
   foreach(alias IN LISTS LIBOMP_ALIASES)
     install(CODE "execute_process(COMMAND \"\${CMAKE_COMMAND}\" -E copy \"${LIBOMP_LIB_FILE}\"
-      \"${alias}${LIBOMP_LIBRARY_SUFFIX}\" WORKING_DIRECTORY \"\${CMAKE_INSTALL_PREFIX}/bin\")")
+      \"${alias}${LIBOMP_LIBRARY_SUFFIX}\" WORKING_DIRECTORY \"\${CMAKE_INSTALL_BINDIR}\")")
     install(CODE "execute_process(COMMAND \"\${CMAKE_COMMAND}\" -E copy \"${LIBOMP_IMP_LIB_FILE}\"
       \"${alias}${CMAKE_STATIC_LIBRARY_SUFFIX}\" WORKING_DIRECTORY \"\${CMAKE_INSTALL_PREFIX}/${OPENMP_INSTALL_LIBDIR}\")")
   endforeach()
diff --git a/openmp/tools/multiplex/CMakeLists.txt b/openmp/tools/multiplex/CMakeLists.txt
--- a/openmp/tools/multiplex/CMakeLists.txt
+++ b/openmp/tools/multiplex/CMakeLists.txt
@@ -4,7 +4,7 @@
   add_library(ompt-multiplex INTERFACE)
   target_include_directories(ompt-multiplex INTERFACE ${CMAKE_CURRENT_SOURCE_DIR})
 
-  install(FILES ompt-multiplex.h DESTINATION include)
+  install(FILES ompt-multiplex.h DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}")
 
   add_subdirectory(tests)
 endif()
diff --git a/polly/CMakeLists.txt b/polly/CMakeLists.txt
--- a/polly/CMakeLists.txt
+++ b/polly/CMakeLists.txt
@@ -1,3 +1,5 @@
+include(GNUInstallDirs)
+
 # Check if this is a in tree build.
 if (NOT DEFINED LLVM_MAIN_SRC_DIR)
   project(Polly)
@@ -124,13 +126,13 @@
 
 if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
   install(DIRECTORY include/
-    DESTINATION include
+    DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
     FILES_MATCHING
     PATTERN "*.h"
     )
 
   install(DIRECTORY ${POLLY_BINARY_DIR}/include/
-    DESTINATION include
+    DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
     FILES_MATCHING
     PATTERN "*.h"
     PATTERN "CMakeFiles" EXCLUDE
diff --git a/polly/cmake/CMakeLists.txt b/polly/cmake/CMakeLists.txt
--- a/polly/cmake/CMakeLists.txt
+++ b/polly/cmake/CMakeLists.txt
@@ -1,5 +1,6 @@
 # Keep this in sync with llvm/cmake/CMakeLists.txt!
 
+include(ExtendPath)
 include(FindPrefixFromConfig)
 
 set(LLVM_INSTALL_PACKAGE_DIR "lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")
@@ -83,17 +84,18 @@
 # Generate PollyConfig.cmake for the install tree.
 unset(POLLY_EXPORTS)
 find_prefix_from_config(POLLY_CONFIG_CODE POLLY_INSTALL_PREFIX "${POLLY_INSTALL_PACKAGE_DIR}")
-set(POLLY_CONFIG_LLVM_CMAKE_DIR "\${POLLY_INSTALL_PREFIX}/${LLVM_INSTALL_PACKAGE_DIR}")
-set(POLLY_CONFIG_CMAKE_DIR "\${POLLY_INSTALL_PREFIX}/${POLLY_INSTALL_PACKAGE_DIR}")
-set(POLLY_CONFIG_LIBRARY_DIRS "\${POLLY_INSTALL_PREFIX}/lib${LLVM_LIBDIR_SUFFIX}")
+extend_path(POLLY_CONFIG_LLVM_CMAKE_DIR "\${POLLY_INSTALL_PREFIX}" "${LLVM_INSTALL_PACKAGE_DIR}")
+extend_path(POLLY_CONFIG_CMAKE_DIR "\${POLLY_INSTALL_PREFIX}" "${POLLY_INSTALL_PACKAGE_DIR}")
+extend_path(POLLY_CONFIG_LIBRARY_DIRS "\${POLLY_INSTALL_PREFIX}" "lib${LLVM_LIBDIR_SUFFIX}")
+extend_path(base_includedir "\${POLLY_INSTALL_PREFIX}" "${CMAKE_INSTALL_INCLUDEDIR}")
 if (POLLY_BUNDLED_ISL)
   set(POLLY_CONFIG_INCLUDE_DIRS
-    "\${POLLY_INSTALL_PREFIX}/include"
-    "\${POLLY_INSTALL_PREFIX}/include/polly"
+    "${base_includedir}"
+    "${base_includedir}/polly"
     )
 else()
   set(POLLY_CONFIG_INCLUDE_DIRS
-    "\${POLLY_INSTALL_PREFIX}/include"
+    "${base_includedir}"
     ${ISL_INCLUDE_DIRS}
     )
 endif()
@@ -110,12 +112,12 @@
 foreach(tgt IN LISTS POLLY_CONFIG_EXPORTED_TARGETS)
   get_target_property(tgt_type ${tgt} TYPE)
   if (tgt_type STREQUAL "EXECUTABLE")
-    set(tgt_prefix "bin/")
+    set(tgt_prefix "${CMAKE_INSTALL_BINDIR}/")
   else()
-    set(tgt_prefix "lib/")
+    set(tgt_prefix "${CMAKE_INSTALL_LIBDIR}/")
   endif()
 
-  set(tgt_path "\${POLLY_INSTALL_PREFIX}/${tgt_prefix}$<TARGET_FILE_NAME:${tgt}>")
+  extend_path(tgt_path "\${POLLY_INSTALL_PREFIX}" "${tgt_prefix}$<TARGET_FILE_NAME:${tgt}>")
 
   if (NOT tgt_type STREQUAL "INTERFACE_LIBRARY")
     set(POLLY_EXPORTS
diff --git a/polly/lib/External/CMakeLists.txt b/polly/lib/External/CMakeLists.txt
--- a/polly/lib/External/CMakeLists.txt
+++ b/polly/lib/External/CMakeLists.txt
@@ -290,7 +290,7 @@
     install(DIRECTORY
       ${ISL_SOURCE_DIR}/include/
       ${ISL_BINARY_DIR}/include/
-      DESTINATION include/polly
+      DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/polly"
       FILES_MATCHING
       PATTERN "*.h"
       PATTERN "CMakeFiles" EXCLUDE
diff --git a/pstl/CMakeLists.txt b/pstl/CMakeLists.txt
--- a/pstl/CMakeLists.txt
+++ b/pstl/CMakeLists.txt
@@ -7,6 +7,8 @@
 #===----------------------------------------------------------------------===##
 cmake_minimum_required(VERSION 3.13.4)
 
+include(GNUInstallDirs)
+
 set(PARALLELSTL_VERSION_FILE "${CMAKE_CURRENT_SOURCE_DIR}/include/pstl/internal/pstl_config.h")
 file(STRINGS "${PARALLELSTL_VERSION_FILE}" PARALLELSTL_VERSION_SOURCE REGEX "#define _PSTL_VERSION .*$")
 string(REGEX REPLACE "#define _PSTL_VERSION (.*)$" "\\1" PARALLELSTL_VERSION_SOURCE "${PARALLELSTL_VERSION_SOURCE}")
@@ -90,10 +92,10 @@
               "${CMAKE_CURRENT_BINARY_DIR}/ParallelSTLConfigVersion.cmake"
         DESTINATION lib/cmake/ParallelSTL)
 install(DIRECTORY include/
-        DESTINATION include
+        DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
         PATTERN "*.in" EXCLUDE)
 install(FILES "${PSTL_CONFIG_SITE_PATH}"
-        DESTINATION include)
+        DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}")
 
 add_custom_target(install-pstl
                   COMMAND "${CMAKE_COMMAND}" -P "${PROJECT_BINARY_DIR}/cmake_install.cmake" -DCOMPONENT=ParallelSTL)