diff --git a/lldb/packages/Python/lldbsuite/test/dotest.py b/lldb/packages/Python/lldbsuite/test/dotest.py
--- a/lldb/packages/Python/lldbsuite/test/dotest.py
+++ b/lldb/packages/Python/lldbsuite/test/dotest.py
@@ -302,6 +302,11 @@
         configuration.sdkroot = seven.get_command_output(
             'xcrun --sdk "%s" --show-sdk-path 2> /dev/null' %
             (args.apple_sdk))
+        if not configuration.sdkroot:
+            logging.error(
+                    'No SDK found with the name %s; aborting...',
+                    args.apple_sdk)
+            sys.exit(-1)
 
     if args.arch:
         configuration.arch = args.arch