diff --git a/lldb/packages/Python/lldbsuite/test/configuration.py b/lldb/packages/Python/lldbsuite/test/configuration.py
--- a/lldb/packages/Python/lldbsuite/test/configuration.py
+++ b/lldb/packages/Python/lldbsuite/test/configuration.py
@@ -48,6 +48,10 @@
 # The overriden dwarf verison.
 dwarf_version = 0
 
+# Any overridden settings.
+# Always disable default dynamic types for testing purposes.
+settings = [('target.prefer-dynamic-value', 'no-dynamic-values')]
+
 # Path to the FileCheck testing tool. Not optional.
 filecheck = None
 
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
@@ -343,6 +343,14 @@
         # that explicitly require no debug info.
         os.environ['CFLAGS'] = '-gdwarf-{}'.format(configuration.dwarf_version)
 
+    if args.settings:
+        for setting in args.settings:
+            if not len(setting) == 1 or not setting[0].count('='):
+                logging.error('"%s" is not a setting in the form "key=value"',
+                              setting[0])
+                sys.exit(-1)
+            configuration.settings.append(setting[0].split('=', 1))
+
     if args.d:
         sys.stdout.write(
             "Suspending the process %d to wait for debugger to attach...\n" %
@@ -765,17 +773,15 @@
             raise
 
 
-def disabledynamics():
+def setSetting(setting, value):
     import lldb
     ci = lldb.DBG.GetCommandInterpreter()
     res = lldb.SBCommandReturnObject()
-    ci.HandleCommand(
-        "setting set target.prefer-dynamic-value no-dynamic-values",
-        res,
-        False)
+    cmd = 'setting set %s %s'%(setting, value)
+    print(cmd)
+    ci.HandleCommand(cmd, res, False)
     if not res.Succeeded():
-        raise Exception('disabling dynamic type support failed')
-
+        raise Exception('failed to run "%s"'%cmd)
 
 # ======================================== #
 #                                          #
@@ -1060,8 +1066,9 @@
     # Now that we have loaded all the test cases, run the whole test suite.
     #
 
-    # Disable default dynamic types for testing purposes
-    disabledynamics()
+    # Set any user-overridden settings.
+    for key, value in configuration.settings:
+        setSetting(key, value)
 
     # Install the control-c handler.
     unittest2.signals.installHandler()
diff --git a/lldb/packages/Python/lldbsuite/test/dotest_args.py b/lldb/packages/Python/lldbsuite/test/dotest_args.py
--- a/lldb/packages/Python/lldbsuite/test/dotest_args.py
+++ b/lldb/packages/Python/lldbsuite/test/dotest_args.py
@@ -116,6 +116,14 @@
         type=int,
         help='Override the DWARF version.')
     group.add_argument(
+        '--setting',
+        metavar='SETTING=VALUE',
+        dest='settings',
+        type=str,
+        nargs=1,
+        action='append',
+        help='Run "setting set SETTING VALUE" before executing any test.')
+    group.add_argument(
         '-s',
         metavar='name',
         help='Specify the name of the dir created to store the session files of tests with errored or failed status. If not specified, the test driver uses the timestamp as the session dir name')