[clang][cmake] Use `GNUInstallDirs` to support custom installation dirs

I am breaking apart D99484 so the cause of build failures is easier to
understand.

Differential Revision: https://reviews.llvm.org/D117419

clang/CMakeLists.txt

@@ -4,7 +4,13 @@ cmake_minimum_required(VERSION 3.13.4)
 # standalone project, using LLVM as an external library:
 if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
   project(Clang)
+  set(CLANG_BUILT_STANDALONE TRUE)
+endif()
 
+# Must go below project(..)
+include(GNUInstallDirs)
+
+if(CLANG_BUILT_STANDALONE)
   set(CMAKE_CXX_STANDARD 14 CACHE STRING "C++ standard to conform to")
   set(CMAKE_CXX_STANDARD_REQUIRED YES)
   set(CMAKE_CXX_EXTENSIONS NO)
@@ -185,8 +191,6 @@ if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
     endif()
   endif()
 
-  set(CLANG_BUILT_STANDALONE TRUE)
-
   set(BACKEND_PACKAGE_STRING "LLVM ${LLVM_PACKAGE_VERSION}")
 else()
   set(BACKEND_PACKAGE_STRING "${PACKAGE_STRING}")
@@ -424,7 +428,7 @@ include_directories(BEFORE
 
 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 +437,7 @@ if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
     )
 
   install(DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/include/clang
-    DESTINATION include
+    DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
     COMPONENT clang-headers
     FILES_MATCHING
     PATTERN "CMakeFiles" EXCLUDE
@@ -453,7 +457,7 @@ if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
 
   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

clang/cmake/modules/AddClang.cmake

@@ -1,3 +1,4 @@
+include(GNUInstallDirs)
 include(LLVMDistributionSupport)
 
 function(clang_tablegen)
@@ -120,7 +121,7 @@ macro(add_clang_library name)
           ${export_to_clangtargets}
           LIBRARY DESTINATION lib${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-${lib}
@@ -159,7 +160,7 @@ macro(add_clang_tool name)
     get_target_export_arg(${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)

clang/cmake/modules/CMakeLists.txt

@@ -1,3 +1,4 @@
+include(ExtendPath)
 include(LLVMDistributionSupport)
 include(FindPrefixFromConfig)
 
@@ -42,8 +43,9 @@ find_prefix_from_config(CLANG_CONFIG_CODE CLANG_INSTALL_PREFIX "${CLANG_INSTALL_
 set(CLANG_CONFIG_CMAKE_DIR "\${CLANG_INSTALL_PREFIX}/${CLANG_INSTALL_PACKAGE_DIR}")
 set(CLANG_CONFIG_LLVM_CMAKE_DIR "\${CLANG_INSTALL_PREFIX}/${LLVM_INSTALL_PACKAGE_DIR}")
 get_config_exports_includes(Clang CLANG_CONFIG_INCLUDE_EXPORTS)
+extend_path(base_includedir "\${CLANG_INSTALL_PREFIX}" "${CMAKE_INSTALL_INCLUDEDIR}")
 set(CLANG_CONFIG_INCLUDE_DIRS
-  "\${CLANG_INSTALL_PREFIX}/include"
+  "${base_includedir}"
   )
 configure_file(
   ${CMAKE_CURRENT_SOURCE_DIR}/ClangConfig.cmake.in

clang/tools/c-index-test/CMakeLists.txt

@@ -49,7 +49,7 @@ if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
     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

clang/tools/clang-format/CMakeLists.txt

@@ -21,20 +21,20 @@ if( LLVM_LIB_FUZZING_ENGINE OR LLVM_USE_SANITIZE_COVERAGE )
 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)

clang/tools/clang-nvlink-wrapper/CMakeLists.txt

@@ -22,4 +22,4 @@ target_link_libraries(clang-nvlink-wrapper
   ${CLANG_NVLINK_WRAPPER_LIB_DEPS}
   )
 
-install(TARGETS clang-nvlink-wrapper RUNTIME DESTINATION bin)
+install(TARGETS clang-nvlink-wrapper RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}")

clang/tools/clang-rename/CMakeLists.txt

@@ -19,8 +19,8 @@ clang_target_link_libraries(clang-rename
   )
 
 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)

clang/tools/libclang/CMakeLists.txt

@@ -186,7 +186,7 @@ endif()
 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

clang/tools/scan-build-py/CMakeLists.txt

@@ -43,7 +43,7 @@ foreach(BinFile ${BinFiles})
                          ${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 @@ foreach(BinFile ${BinFiles})
                          ${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 @@ foreach(lib ${LibExecs})
                      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()
 

clang/tools/scan-build/CMakeLists.txt

@@ -47,7 +47,7 @@ if(CLANG_INSTALL_SCANBUILD)
                        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 @@ if(CLANG_INSTALL_SCANBUILD)
                        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 @@ if(CLANG_INSTALL_SCANBUILD)
                        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()
 

clang/tools/scan-view/CMakeLists.txt

@@ -20,7 +20,7 @@ if(CLANG_INSTALL_SCANVIEW)
                        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 @@ if(CLANG_INSTALL_SCANVIEW)
                        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()
 

clang/utils/hmaptool/CMakeLists.txt

@@ -10,7 +10,7 @@ add_custom_command(OUTPUT ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin/${CLANG_HM
 
 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})