nac3/nix/llvm/gnu-install-dirs.patch

diff --git a/CMakeLists.txt b/CMakeLists.txt
index fec956091cd5..5a766f5c5d7c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -303,6 +303,9 @@ set(LLVM_EXAMPLES_INSTALL_DIR "examples" CACHE STRING
     "Path for examples subdirectory (enabled by LLVM_BUILD_EXAMPLES=ON) (defaults to 'examples')")
 mark_as_advanced(LLVM_EXAMPLES_INSTALL_DIR)
 
+set(LLVM_INSTALL_CMAKE_DIR "${CMAKE_INSTALL_LIBDIR}${LLVM_LIBDIR_SUFFIX}/cmake/llvm" CACHE STRING
+	"Path for CMake subdirectory (defaults to lib/cmake/llvm)" )
+
 # 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${LLVM_LIBDIR_SUFFIX})
diff --git a/cmake/modules/AddLLVM.cmake b/cmake/modules/AddLLVM.cmake
index fed1fec7d72e..4baed19b9e98 100644
--- a/cmake/modules/AddLLVM.cmake
+++ b/cmake/modules/AddLLVM.cmake
@@ -838,8 +838,8 @@ macro(add_llvm_library name)
       get_target_export_arg(${name} LLVM export_to_llvmexports ${umbrella})
       install(TARGETS ${name}
               ${export_to_llvmexports}
-              LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX} COMPONENT ${name}
-              ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX} COMPONENT ${name}
+              LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}${LLVM_LIBDIR_SUFFIX}" COMPONENT ${name}
+              ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}${LLVM_LIBDIR_SUFFIX}" COMPONENT ${name}
               RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}" COMPONENT ${name})
 
       if (NOT LLVM_ENABLE_IDE)
@@ -1056,7 +1056,7 @@ function(process_llvm_pass_plugins)
           "set(LLVM_STATIC_EXTENSIONS ${LLVM_STATIC_EXTENSIONS})")
       install(FILES
           ${llvm_cmake_builddir}/LLVMConfigExtensions.cmake
-          DESTINATION ${LLVM_INSTALL_PACKAGE_DIR}
+          DESTINATION ${LLVM_INSTALL_CMAKE_DIR}
           COMPONENT cmake-exports)
 
       set(ExtensionDef "${LLVM_BINARY_DIR}/include/llvm/Support/Extension.def")
@@ -1902,7 +1902,7 @@ 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 lib${LLVM_LIBDIR_SUFFIX})
+  set(output_dir ${CMAKE_INSTALL_FULL_LIBDIR}${LLVM_LIBDIR_SUFFIX})
   if(WIN32 AND "${type}" STREQUAL "SHARED")
     set(output_dir bin)
   endif()
@@ -1913,7 +1913,7 @@ function(llvm_install_library_symlink name dest type)
 
 endfunction()
 
-function(llvm_install_symlink name dest)
+function(llvm_install_symlink name dest output_dir)
   cmake_parse_arguments(ARG "ALWAYS_GENERATE" "COMPONENT" "" ${ARGN})
   foreach(path ${CMAKE_MODULE_PATH})
     if(EXISTS ${path}/LLVMInstallSymlink.cmake)
@@ -1936,7 +1936,7 @@ function(llvm_install_symlink name dest)
   set(full_dest ${dest}${CMAKE_EXECUTABLE_SUFFIX})
 
   install(SCRIPT ${INSTALL_SYMLINK}
-          CODE "install_symlink(${full_name} ${full_dest} ${LLVM_TOOLS_INSTALL_DIR})"
+          CODE "install_symlink(${full_name} ${full_dest} ${output_dir})"
           COMPONENT ${component})
 
   if (NOT LLVM_ENABLE_IDE AND NOT ARG_ALWAYS_GENERATE)
@@ -2019,7 +2019,8 @@ function(add_llvm_tool_symlink link_name target)
     endif()
 
     if ((TOOL_IS_TOOLCHAIN OR NOT LLVM_INSTALL_TOOLCHAIN_ONLY) AND LLVM_BUILD_TOOLS)
-      llvm_install_symlink(${link_name} ${target})
+      GNUInstallDirs_get_absolute_install_dir(output_dir LLVM_TOOLS_INSTALL_DIR)
+      llvm_install_symlink(${link_name} ${target} ${output_dir})
     endif()
   endif()
 endfunction()
@@ -2148,9 +2149,9 @@ function(llvm_setup_rpath name)
     # Since BUILD_SHARED_LIBS is only recommended for use by developers,
     # hardcode the rpath to build/install lib dir first in this mode.
     # FIXME: update this when there is better solution.
-    set(_install_rpath "${LLVM_LIBRARY_OUTPUT_INTDIR}" "${CMAKE_INSTALL_PREFIX}/lib${LLVM_LIBDIR_SUFFIX}" ${extra_libdir})
+    set(_install_rpath "${LLVM_LIBRARY_OUTPUT_INTDIR}" "${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR}${LLVM_LIBDIR_SUFFIX}" ${extra_libdir})
   elseif(UNIX)
-    set(_install_rpath "\$ORIGIN/../lib${LLVM_LIBDIR_SUFFIX}" ${extra_libdir})
+    set(_install_rpath "\$ORIGIN/../${CMAKE_INSTALL_LIBDIR}${LLVM_LIBDIR_SUFFIX}" ${extra_libdir})
     if(${CMAKE_SYSTEM_NAME} MATCHES "(FreeBSD|DragonFly)")
       set_property(TARGET ${name} APPEND_STRING PROPERTY
                    LINK_FLAGS " -Wl,-z,origin ")
diff --git a/cmake/modules/AddOCaml.cmake b/cmake/modules/AddOCaml.cmake
index 891c9e6d618c..8d963f3b0069 100644
--- a/cmake/modules/AddOCaml.cmake
+++ b/cmake/modules/AddOCaml.cmake
@@ -147,9 +147,9 @@ function(add_ocaml_library name)
   endforeach()
 
   if( APPLE )
-    set(ocaml_rpath "@executable_path/../../../lib${LLVM_LIBDIR_SUFFIX}")
+    set(ocaml_rpath "@executable_path/../../../${CMAKE_INSTALL_LIBDIR}${LLVM_LIBDIR_SUFFIX}")
   elseif( UNIX )
-    set(ocaml_rpath "\\$ORIGIN/../../../lib${LLVM_LIBDIR_SUFFIX}")
+    set(ocaml_rpath "\\$ORIGIN/../../../${CMAKE_INSTALL_LIBDIR}${LLVM_LIBDIR_SUFFIX}")
   endif()
   list(APPEND ocaml_flags "-ldopt" "-Wl,-rpath,${ocaml_rpath}")
 
diff --git a/cmake/modules/CMakeLists.txt b/cmake/modules/CMakeLists.txt
index cea0c1df0a14..eedcd9450312 100644
--- a/cmake/modules/CMakeLists.txt
+++ b/cmake/modules/CMakeLists.txt
@@ -2,7 +2,7 @@ include(ExtendPath)
 include(LLVMDistributionSupport)
 include(FindPrefixFromConfig)
 
-set(LLVM_INSTALL_PACKAGE_DIR lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm)
+set(LLVM_INSTALL_PACKAGE_DIR ${LLVM_INSTALL_CMAKE_DIR} CACHE STRING "Path for CMake subdirectory (defaults to 'cmake/llvm')")
 set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/${LLVM_INSTALL_PACKAGE_DIR}")
 
 # First for users who use an installed LLVM, create the LLVMExports.cmake file.
@@ -122,7 +122,7 @@ set(LLVM_CONFIG_INCLUDE_DIRS
   )
 list(REMOVE_DUPLICATES LLVM_CONFIG_INCLUDE_DIRS)
 
-extend_path(LLVM_CONFIG_LIBRARY_DIR "\${LLVM_INSTALL_PREFIX}" "lib\${LLVM_LIBDIR_SUFFIX}")
+extend_path(LLVM_CONFIG_LIBRARY_DIR "\${LLVM_INSTALL_PREFIX}" "${CMAKE_INSTALL_LIBDIR}\${LLVM_LIBDIR_SUFFIX}")
 set(LLVM_CONFIG_LIBRARY_DIRS
   "${LLVM_CONFIG_LIBRARY_DIR}"
   # FIXME: Should there be other entries here?
diff --git a/cmake/modules/LLVMInstallSymlink.cmake b/cmake/modules/LLVMInstallSymlink.cmake
index b5c35f706cb7..9261ab797de6 100644
--- a/cmake/modules/LLVMInstallSymlink.cmake
+++ b/cmake/modules/LLVMInstallSymlink.cmake
@@ -6,7 +6,7 @@ include(GNUInstallDirs)
 
 function(install_symlink name target outdir)
   set(DESTDIR $ENV{DESTDIR})
-  set(bindir "${DESTDIR}${CMAKE_INSTALL_PREFIX}/${outdir}")
+  set(bindir "${DESTDIR}${outdir}/")
 
   message(STATUS "Creating ${name}")
 
diff --git a/docs/CMake.rst b/docs/CMake.rst
index 044ec8a4d39d..504d0eac3ade 100644
--- a/docs/CMake.rst
+++ b/docs/CMake.rst
@@ -224,7 +224,7 @@ description is in `LLVM-related variables`_ below.
 **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``.
+  to install libraries to ``/usr/lib64``. See also ``CMAKE_INSTALL_LIBDIR``.
 
 **LLVM_PARALLEL_{COMPILE,LINK}_JOBS**:STRING
   Building the llvm toolchain can use a lot of resources, particularly
@@ -910,9 +910,11 @@ the ``cmake`` command or by setting it directly in ``ccmake`` or ``cmake-gui``).
 
 This file is available in two different locations.
 
-* ``<INSTALL_PREFIX>/lib/cmake/llvm/LLVMConfig.cmake`` where
-  ``<INSTALL_PREFIX>`` is the install prefix of an installed version of LLVM.
-  On Linux typically this is ``/usr/lib/cmake/llvm/LLVMConfig.cmake``.
+* ``<LLVM_INSTALL_PACKAGE_DIR>LLVMConfig.cmake`` where
+  ``<LLVM_INSTALL_PACKAGE_DIR>`` is the location where LLVM CMake modules are
+  installed as part of an installed version of LLVM. This is typically
+  ``cmake/llvm/`` within the lib directory. On Linux, this is typically
+  ``/usr/lib/cmake/llvm/LLVMConfig.cmake``.
 
 * ``<LLVM_BUILD_ROOT>/lib/cmake/llvm/LLVMConfig.cmake`` where
   ``<LLVM_BUILD_ROOT>`` is the root of the LLVM build tree. **Note: this is only
diff --git a/include/llvm/CMakeLists.txt b/include/llvm/CMakeLists.txt
index b46319f24fc8..2feabd1954e4 100644
--- a/include/llvm/CMakeLists.txt
+++ b/include/llvm/CMakeLists.txt
@@ -5,5 +5,5 @@ add_subdirectory(Frontend)
 # If we're doing an out-of-tree build, copy a module map for generated
 # header files into the build area.
 if (NOT "${CMAKE_SOURCE_DIR}" STREQUAL "${CMAKE_BINARY_DIR}")
-  configure_file(module.modulemap.build module.modulemap COPYONLY)
+  configure_file(module.modulemap.build ${LLVM_INCLUDE_DIR}/module.modulemap COPYONLY)
 endif (NOT "${CMAKE_SOURCE_DIR}" STREQUAL "${CMAKE_BINARY_DIR}")
diff --git a/tools/llvm-config/BuildVariables.inc.in b/tools/llvm-config/BuildVariables.inc.in
index abbb8a450da6..70c497be12f5 100644
--- a/tools/llvm-config/BuildVariables.inc.in
+++ b/tools/llvm-config/BuildVariables.inc.in
@@ -23,7 +23,10 @@
 #define LLVM_CXXFLAGS "@LLVM_CXXFLAGS@"
 #define LLVM_BUILDMODE "@LLVM_BUILDMODE@"
 #define LLVM_LIBDIR_SUFFIX "@LLVM_LIBDIR_SUFFIX@"
+#define LLVM_INSTALL_BINDIR "@CMAKE_INSTALL_BINDIR@"
+#define LLVM_INSTALL_LIBDIR "@CMAKE_INSTALL_LIBDIR@"
 #define LLVM_INSTALL_INCLUDEDIR "@CMAKE_INSTALL_INCLUDEDIR@"
+#define LLVM_INSTALL_CMAKEDIR "@LLVM_INSTALL_CMAKE_DIR@"
 #define LLVM_TARGETS_BUILT "@LLVM_TARGETS_BUILT@"
 #define LLVM_SYSTEM_LIBS "@LLVM_SYSTEM_LIBS@"
 #define LLVM_BUILD_SYSTEM "@LLVM_BUILD_SYSTEM@"
diff --git a/tools/llvm-config/llvm-config.cpp b/tools/llvm-config/llvm-config.cpp
index 8ed88f33ead4..5e7184bab90d 100644
--- a/tools/llvm-config/llvm-config.cpp
+++ b/tools/llvm-config/llvm-config.cpp
@@ -363,12 +363,20 @@ int main(int argc, char **argv) {
       ActiveIncludeDir = std::string(Path.str());
     }
     {
-      SmallString<256> Path(LLVM_TOOLS_INSTALL_DIR);
+      SmallString<256> Path(LLVM_INSTALL_BINDIR);
       sys::fs::make_absolute(ActivePrefix, Path);
       ActiveBinDir = std::string(Path.str());
     }
-    ActiveLibDir = ActivePrefix + "/lib" + LLVM_LIBDIR_SUFFIX;
-    ActiveCMakeDir = ActiveLibDir + "/cmake/llvm";
+    {
+      SmallString<256> Path(LLVM_INSTALL_LIBDIR LLVM_LIBDIR_SUFFIX);
+      sys::fs::make_absolute(ActivePrefix, Path);
+      ActiveLibDir = std::string(Path.str());
+    }
+    {
+      SmallString<256> Path(LLVM_INSTALL_CMAKEDIR);
+      sys::fs::make_absolute(ActivePrefix, Path);
+      ActiveCMakeDir = std::string(Path.str());
+    }
     ActiveIncludeOption = "-I" + ActiveIncludeDir;
   }