Index: llvm/CMakeLists.txt
===================================================================
--- llvm/CMakeLists.txt
+++ llvm/CMakeLists.txt
@@ -439,6 +439,9 @@
 option(LLVM_FORCE_USE_OLD_TOOLCHAIN
        "Set to ON to force using an old, unsupported host toolchain." OFF)
 
+set(LLVM_LOCAL_RPATH "" CACHE FILEPATH
+  "If set, an absolute path added as rpath on binaries that do not already contain an executable-relative rpath.")
+
 option(LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN
        "Set to ON to only warn when using a toolchain which is about to be deprecated, instead of emitting an error." OFF)
 
Index: llvm/cmake/modules/AddLLVM.cmake
===================================================================
--- llvm/cmake/modules/AddLLVM.cmake
+++ llvm/cmake/modules/AddLLVM.cmake
@@ -821,6 +821,10 @@
 
   if(NOT ARG_NO_INSTALL_RPATH)
     llvm_setup_rpath(${name})
+  elseif (LLVM_LOCAL_RPATH)
+    set_target_properties(${name} PROPERTIES
+                          BUILD_WITH_INSTALL_RPATH On
+                          INSTALL_RPATH "${LLVM_LOCAL_RPATH}")
   endif()
 
   if(DEFINED windows_resource_file)
Index: llvm/docs/GettingStarted.rst
===================================================================
--- llvm/docs/GettingStarted.rst
+++ llvm/docs/GettingStarted.rst
@@ -340,6 +340,16 @@
 from the loader similar to ``libstdc++.so.6: version `GLIBCXX_3.4.20' not
 found``. This means you need to tweak the -rpath linker flag.
 
+This method will add an absolute path to the rpath of all executables. That's
+fine for local development. If you want to distribute the binaries you build
+so that they can run on older systems, copy ``libstdc++.so.6`` into the
+``lib/`` directory.  All of LLVM's shipping binaries have an rpath pointing at
+``$ORIGIN/../lib``, so they will find ``libstdc++.so.6`` there.  Non-distributed
+binaries don't have an rpath set and won't find ``libstdc++.so.6``. Pass
+``-DLLVM_LOCAL_RPATH="$HOME/toolchains/lib64"`` to cmake to add an absolute
+path to ``libstdc++.so.6`` as above. Since these binaries are not distributed,
+having an absolute local path is fine for them.
+
 When you build Clang, you will need to give *it* access to modern C++
 standard library in order to use it as your new host in part of a bootstrap.
 There are two easy ways to do this, either build (and install) libc++ along