diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -677,9 +677,10 @@
   HelpText<"Filename to write DOT-formatted header dependencies to">;
 def module_dependency_dir : Separate<["-"], "module-dependency-dir">,
   Flags<[CC1Option]>, HelpText<"Directory to dump module dependencies to">;
-def dsym_dir : JoinedOrSeparate<["-"], "dsym-dir">,
+def dsym_dir : Separate<["--"], "dsym-dir">,
   Flags<[DriverOption, RenderAsInput]>,
   HelpText<"Directory to output dSYM's (if any) to">, MetaVarName<"<dir>">;
+def dsym_dir_EQ : Joined<["--"], "dsym-dir=">, Alias<dsym_dir>;
 def dumpmachine : Flag<["-"], "dumpmachine">;
 def dumpspecs : Flag<["-"], "dumpspecs">, Flags<[Unsupported]>;
 def dumpversion : Flag<["-"], "dumpversion">;
diff --git a/clang/test/Driver/darwin-dsymutil.c b/clang/test/Driver/darwin-dsymutil.c
--- a/clang/test/Driver/darwin-dsymutil.c
+++ b/clang/test/Driver/darwin-dsymutil.c
@@ -35,7 +35,7 @@
 // RUN:           -check-prefix=CHECK-OUTPUT-NAME < %t %s
 //
 // RUN: %clang -target x86_64-apple-darwin10 -ccc-print-bindings \
-// RUN:   -o bar/foo -dsym-dir external %s -g 2> %t
+// RUN:   -o bar/foo --dsym-dir external %s -g 2> %t
 // RUN: FileCheck -Doutfile=bar/foo -Ddsymfile=external/foo.dSYM \
 // RUN:           -check-prefix=CHECK-OUTPUT-NAME < %t %s
 //
diff --git a/llvm/cmake/modules/AddLLVM.cmake b/llvm/cmake/modules/AddLLVM.cmake
--- a/llvm/cmake/modules/AddLLVM.cmake
+++ b/llvm/cmake/modules/AddLLVM.cmake
@@ -1981,21 +1981,29 @@
     set_property(TARGET ${name} APPEND_STRING PROPERTY
       LINK_FLAGS " ${empty_src}")
     if(LLVM_EXTERNALIZE_DEBUGINFO_OUTPUT_DIR)
-      # clang can currently only emit dSYM's to the same directory as the output
-      # binary. Workaround this by moving it after the build.
-      set(output_name "$<TARGET_FILE_NAME:${name}>.${file_ext}")
-      set(output_path "${LLVM_EXTERNALIZE_DEBUGINFO_OUTPUT_DIR}/${output_name}")
-      add_custom_command(TARGET ${name} POST_BUILD
-        COMMAND ${CMAKE_COMMAND} -E make_directory "${LLVM_EXTERNALIZE_DEBUGINFO_OUTPUT_DIR}"
-        # Remove any old versions if present
-        COMMAND ${CMAKE_COMMAND} -E rm "-rf" "${output_path}"
-        # Move the dSYM clang emitted next to the output binary where we want it
-        # to be.
-        COMMAND ${CMAKE_COMMAND}
-                    -DFROM="$<TARGET_FILE:${name}>.${file_ext}"
-                    -DTO="${output_path}"
-                    -P ${LLVM_CMAKE_PATH}/MoveIfExists.cmake
-      )
+      check_cxx_compiler_flag("--dsym-dir=foo" HAS_DSYM_DIR)
+      if (HAS_DSYM_DIR)
+        set_property(TARGET ${name} APPEND_STRING PROPERTY
+                     LINK_FLAGS " --dsym-dir=${LLVM_EXTERNALIZE_DEBUGINFO_OUTPUT_DIR}")
+        add_custom_command(TARGET ${name} PRE_BUILD
+          COMMAND ${CMAKE_COMMAND} -E make_directory "${LLVM_EXTERNALIZE_DEBUGINFO_OUTPUT_DIR}")
+      else()
+        # clang can currently only emit dSYM's to the same directory as the output
+        # binary. Workaround this by moving it after the build.
+        set(output_name "$<TARGET_FILE_NAME:${name}>.${file_ext}")
+        set(output_path "${LLVM_EXTERNALIZE_DEBUGINFO_OUTPUT_DIR}/${output_name}")
+        add_custom_command(TARGET ${name} POST_BUILD
+          COMMAND ${CMAKE_COMMAND} -E make_directory "${LLVM_EXTERNALIZE_DEBUGINFO_OUTPUT_DIR}"
+          # Remove any old versions if present
+          COMMAND ${CMAKE_COMMAND} -E rm "-rf" "${output_path}"
+          # Move the dSYM clang emitted next to the output binary where we want it
+          # to be.
+          COMMAND ${CMAKE_COMMAND}
+                      -DFROM="$<TARGET_FILE:${name}>.${file_ext}"
+                      -DTO="${output_path}"
+                      -P ${LLVM_CMAKE_PATH}/MoveIfExists.cmake
+        )
+      endif()
     endif()
     add_custom_command(TARGET ${name} POST_BUILD
       COMMAND ${strip_command}