diff --git a/source-builder/sb/defaults.py b/source-builder/sb/defaults.py
index 4f38e73..939b902 100644
--- a/source-builder/sb/defaults.py
+++ b/source-builder/sb/defaults.py
@@ -607,7 +607,7 @@ def load(args, optargs = None):
     command line.
     """
     import copy
-    d = copy.deepcopy(defaults)
+    d = copy.copy(defaults)
     overrides = None
     if os.name == 'nt':
         import windows
diff --git a/source-builder/sb/reports.py b/source-builder/sb/reports.py
index bbb42f4..a3ab4e8 100644
--- a/source-builder/sb/reports.py
+++ b/source-builder/sb/reports.py
@@ -308,8 +308,8 @@ class report:
     def buildset(self, name):
         self.bset_nesting += 1
         self.buildset_start(name)
-        _opts = copy.deepcopy(self.opts)
-        _defaults = copy.deepcopy(self.defaults)
+        _opts = copy.copy(self.opts)
+        _defaults = copy.copy(self.defaults)
         bset = setbuilder.buildset(name,
                                    _configs = self.configs,
                                    _defaults = _defaults,
diff --git a/source-builder/sb/setbuilder.py b/source-builder/sb/setbuilder.py
index 683edbb..8e2e77d 100644
--- a/source-builder/sb/setbuilder.py
+++ b/source-builder/sb/setbuilder.py
@@ -283,8 +283,8 @@ class buildset:
                     # defaults so we do not contaminate one configuration with
                     # another.
                     #
-                    _opts = copy.deepcopy(self.opts)
-                    _defaults = copy.deepcopy(self.defaults)
+                    _opts = copy.copy(self.opts)
+                    _defaults = copy.copy(self.defaults)
                     if configs[s].endswith('.bset'):
                         bs = buildset(configs[s],
                                       _configs = self.configs,