Index: runtimes/CMakeLists.txt
===================================================================
--- runtimes/CMakeLists.txt
+++ runtimes/CMakeLists.txt
@@ -45,7 +45,9 @@
   endforeach()
   if(compiler_rt_path)
     list(REMOVE_ITEM runtimes ${compiler_rt_path})
-    list(INSERT runtimes 0 ${compiler_rt_path})
+    if(NOT LLVM_BUILD_COMPILER_RT)
+      list(INSERT runtimes 0 ${compiler_rt_path})
+    endif()
   endif()
 
   # LLVMConfig.cmake contains a bunch of CMake variables from the LLVM build.
@@ -87,6 +89,10 @@
   set(CMAKE_REQUIRED_FLAGS ${SAFE_CMAKE_REQUIRED_FLAGS})
   set(CMAKE_REQUIRED_LIBRARIES ${SAFE_CMAKE_REQUIRED_LIBRARIES})
 
+  if(NOT LLVM_RUNTIMES_PREFIX)
+    set(LLVM_RUNTIMES_PREFIX "${LLVM_RUNTIMES_TARGET}")
+  endif()
+
   foreach(entry ${runtimes})
     get_filename_component(projName ${entry} NAME)
 
@@ -98,7 +104,7 @@
 
     if(LLVM_RUNTIMES_TARGET)
       if(NOT "${entry}" MATCHES "compiler-rt")
-        set(${canon_name}_INSTALL_PREFIX "lib/${LLVM_RUNTIMES_TARGET}/" CACHE STRING "" FORCE)
+        set(${canon_name}_INSTALL_PREFIX "lib/${LLVM_RUNTIMES_PREFIX}/" CACHE STRING "" FORCE)
       endif()
     endif()
 
@@ -118,9 +124,9 @@
 
     if(LLVM_RUNTIMES_TARGET)
       if(NOT "${entry}" MATCHES "compiler-rt")
-        set(LLVM_BINARY_DIR "${LLVM_LIBRARY_DIR}/${LLVM_RUNTIMES_TARGET}")
-        set(LLVM_LIBRARY_OUTPUT_INTDIR "${LLVM_LIBRARY_DIR}/${LLVM_RUNTIMES_TARGET}/lib")
-        set(LLVM_RUNTIME_OUTPUT_INTDIR "${LLVM_TOOLS_BINARY_DIR}/${LLVM_RUNTIMES_TARGET}")
+        set(LLVM_BINARY_DIR "${LLVM_LIBRARY_DIR}/${LLVM_RUNTIMES_PREFIX}")
+        set(LLVM_LIBRARY_OUTPUT_INTDIR "${LLVM_LIBRARY_DIR}/${LLVM_RUNTIMES_PREFIX}/lib")
+        set(LLVM_RUNTIME_OUTPUT_INTDIR "${LLVM_TOOLS_BINARY_DIR}/${LLVM_RUNTIMES_PREFIX}")
       endif()
     endif()
 
@@ -282,7 +288,7 @@
 
   # runtime_register_target(target)
   #   Utility function to register external runtime target.
-  function(runtime_register_target target)
+  function(runtime_register_target target compiler_target)
     if(target STREQUAL LLVM_DEFAULT_TARGET_TRIPLE)
       include(${LLVM_BINARY_DIR}/runtimes/Components.cmake OPTIONAL)
       set_property(DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS ${LLVM_BINARY_DIR}/runtimes/Components.cmake)
@@ -291,11 +297,9 @@
       set_property(DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS ${LLVM_BINARY_DIR}/runtimes/${target}/Components.cmake)
     endif()
 
-    string(REPLACE "/" ";" target_list ${target_components})
-    list(GET target_list 0 target)
-    list(LENGTH target_list target_list_len)
-    if(${target_list_len} GREATER 1)
-      list(GET target_list 1 target_variant)
+    set(${target}_deps ${deps})
+    if(NOT target STREQUAL compiler_target)
+      list(APPEND ${target}_deps runtimes-${compiler_target})
     endif()
 
     foreach(runtime_name ${runtime_names})
@@ -334,14 +338,14 @@
 
     llvm_ExternalProject_Add(runtimes-${target}
                              ${CMAKE_CURRENT_SOURCE_DIR}
-                             DEPENDS ${deps}
+                             DEPENDS ${${target}_deps}
                              # Builtins were built separately above
                              CMAKE_ARGS -DCOMPILER_RT_BUILD_BUILTINS=Off
                                         -DLLVM_INCLUDE_TESTS=${LLVM_INCLUDE_TESTS}
                                         -DLLVM_LIBRARY_DIR=${LLVM_LIBRARY_DIR}
-                                        -DCMAKE_C_COMPILER_TARGET=${target}
-                                        -DCMAKE_CXX_COMPILER_TARGET=${target}
-                                        -DCMAKE_ASM_COMPILER_TARGET=${target}
+                                        -DCMAKE_C_COMPILER_TARGET=${compiler_target}
+                                        -DCMAKE_CXX_COMPILER_TARGET=${compiler_target}
+                                        -DCMAKE_ASM_COMPILER_TARGET=${compiler_target}
                                         -DCMAKE_C_COMPILER_WORKS=ON
                                         -DCMAKE_CXX_COMPILER_WORKS=ON
                                         -DCMAKE_ASM_COMPILER_WORKS=ON
@@ -406,7 +410,15 @@
           set(target ${LLVM_DEFAULT_TARGET_TRIPLE})
         endif()
 
-        runtime_register_target(${target})
+        set(compiler_target ${target})
+        string(REPLACE ":" ";" target_list ${target})
+        list(GET target_list 0 target)
+        list(LENGTH target_list target_list_len)
+        if(${target_list_len} GREATER 1)
+          list(GET target_list 1 compiler_target)
+        endif()
+
+        runtime_register_target(${target} ${compiler_target})
 
         add_dependencies(runtimes runtimes-${target})
         add_dependencies(runtimes-configure runtimes-${target}-configure)