Index: scripts/Xcode/build-llvm.py
===================================================================
--- scripts/Xcode/build-llvm.py
+++ scripts/Xcode/build-llvm.py
@@ -3,6 +3,7 @@
 import errno
 import hashlib
 import os
+import platform
 import subprocess
 import sys
 
@@ -243,6 +244,23 @@
         "/opt/local/bin",
         os.path.join(os.path.expanduser("~"), "bin")
     ]
+
+    if platform.system() == "Darwin":
+        # Add locations where an official CMake.app package may be installed.
+        extra_cmake_dirs.extend([
+           os.path.join(
+               os.path.expanduser("~"),
+               "Applications",
+               "CMake.app",
+               "Contents",
+               "bin"),
+           os.path.join(
+               os.sep,
+               "Applications",
+               "CMake.app",
+               "Contents",
+               "bin")])
+
     cmake_binary = find_executable_in_paths("cmake", extra_cmake_dirs)
     if cmake_binary:
         # We found it in one of the usual places.  Use that.