diff --git a/clang/cmake/caches/Fuchsia-stage2.cmake b/clang/cmake/caches/Fuchsia-stage2.cmake
--- a/clang/cmake/caches/Fuchsia-stage2.cmake
+++ b/clang/cmake/caches/Fuchsia-stage2.cmake
@@ -86,7 +86,7 @@
   set(RUNTIMES_${target}_LLVM_ENABLE_RUNTIMES "compiler-rt;libcxx" CACHE STRING "")
 endif()
 
-foreach(target aarch64-unknown-linux-gnu;armv7-unknown-linux-gnueabihf;i386-unknown-linux-gnu;x86_64-unknown-linux-gnu)
+foreach(target aarch64-linux-gnu;armv7-linux-gnueabihf;i386-linux-gnu;x86_64-linux-gnu)
   if(LINUX_${target}_SYSROOT)
     # Set the per-target builtins options.
     list(APPEND BUILTIN_TARGETS "${target}")
diff --git a/compiler-rt/lib/builtins/CMakeLists.txt b/compiler-rt/lib/builtins/CMakeLists.txt
--- a/compiler-rt/lib/builtins/CMakeLists.txt
+++ b/compiler-rt/lib/builtins/CMakeLists.txt
@@ -35,6 +35,19 @@
   if (NOT LLVM_RUNTIMES_BUILD)
     load_llvm_config()
   endif()
+  if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
+    set(CXX_TARGET_TRIPLE ${CMAKE_CXX_COMPILER} --target=${LLVM_RUNTIME_TRIPLE} -print-target-triple)
+    execute_process(COMMAND ${CXX_TARGET_TRIPLE}
+      RESULT_VARIABLE result
+      OUTPUT_VARIABLE output
+      OUTPUT_STRIP_TRAILING_WHITESPACE)
+    if(result EQUAL 0)
+      set(LLVM_RUNTIME_TRIPLE ${output})
+    else()
+      string(REPLACE ";" " " CXX_TARGET_TRIPLE "${CXX_TARGET_TRIPLE}")
+      message(WARNING "Failed to execute `${CXX_TARGET_TRIPLE}` to normalize target triple.")
+    endif()
+  endif()
   construct_compiler_rt_default_triple()
 
   include(SetPlatformToolchainTools)
diff --git a/runtimes/CMakeLists.txt b/runtimes/CMakeLists.txt
--- a/runtimes/CMakeLists.txt
+++ b/runtimes/CMakeLists.txt
@@ -164,6 +164,20 @@
 set(LLVM_RUNTIME_TRIPLE "${LLVM_HOST_TRIPLE}" CACHE STRING
   "Triple used as runtime instrallation path.")
 
+if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
+  set(CXX_TARGET_TRIPLE ${CMAKE_CXX_COMPILER} --target=${LLVM_RUNTIME_TRIPLE} -print-target-triple)
+  execute_process(COMMAND ${CXX_TARGET_TRIPLE}
+    RESULT_VARIABLE result
+    OUTPUT_VARIABLE output
+    OUTPUT_STRIP_TRAILING_WHITESPACE)
+  if(result EQUAL 0)
+    set(LLVM_RUNTIME_TRIPLE ${output})
+  else()
+    string(REPLACE ";" " " CXX_TARGET_TRIPLE "${CXX_TARGET_TRIPLE}")
+    message(WARNING "Failed to execute `${CXX_TARGET_TRIPLE}` to normalize target triple.")
+  endif()
+endif()
+
 option(LLVM_INCLUDE_TESTS "Generate build targets for the runtimes unit tests." ON)
 option(LLVM_INCLUDE_DOCS "Generate build targets for the runtimes documentation." ON)
 option(LLVM_ENABLE_SPHINX "Use Sphinx to generate the runtimes documentation." OFF)