diff --git a/bitbake/lib/bb/siggen.py b/bitbake/lib/bb/siggen.py
index 50e4558611..8861337b92 100644
--- a/bitbake/lib/bb/siggen.py
+++ b/bitbake/lib/bb/siggen.py
@@ -331,12 +331,12 @@ def compare_sigfiles(a, b, recursecb = None):
         return changed, added, removed
 
     if 'basewhitelist' in a_data and a_data['basewhitelist'] != b_data['basewhitelist']:
-        output.append("basewhitelist changed from %s to %s" % (a_data['basewhitelist'], b_data['basewhitelist']))
+        output.append("basewhitelist changed from '%s' to '%s'" % (a_data['basewhitelist'], b_data['basewhitelist']))
         if a_data['basewhitelist'] and b_data['basewhitelist']:
             output.append("changed items: %s" % a_data['basewhitelist'].symmetric_difference(b_data['basewhitelist']))
 
     if 'taskwhitelist' in a_data and a_data['taskwhitelist'] != b_data['taskwhitelist']:
-        output.append("taskwhitelist changed from %s to %s" % (a_data['taskwhitelist'], b_data['taskwhitelist']))
+        output.append("taskwhitelist changed from '%s' to '%s'" % (a_data['taskwhitelist'], b_data['taskwhitelist']))
         if a_data['taskwhitelist'] and b_data['taskwhitelist']:
             output.append("changed items: %s" % a_data['taskwhitelist'].symmetric_difference(b_data['taskwhitelist']))
 
@@ -349,7 +349,7 @@ def compare_sigfiles(a, b, recursecb = None):
     changed, added, removed = dict_diff(a_data['gendeps'], b_data['gendeps'], a_data['basewhitelist'] & b_data['basewhitelist'])
     if changed:
         for dep in changed:
-            output.append("List of dependencies for variable %s changed from %s to %s" % (dep, a_data['gendeps'][dep], b_data['gendeps'][dep]))
+            output.append("List of dependencies for variable %s changed from '%s' to '%s'" % (dep, a_data['gendeps'][dep], b_data['gendeps'][dep]))
             if a_data['gendeps'][dep] and b_data['gendeps'][dep]:
                 output.append("changed items: %s" % a_data['gendeps'][dep].symmetric_difference(b_data['gendeps'][dep]))
     if added:
@@ -363,7 +363,7 @@ def compare_sigfiles(a, b, recursecb = None):
     changed, added, removed = dict_diff(a_data['varvals'], b_data['varvals'])
     if changed:
         for dep in changed:
-            output.append("Variable %s value changed from %s to %s" % (dep, a_data['varvals'][dep], b_data['varvals'][dep]))
+            output.append("Variable %s value changed from '%s' to '%s'" % (dep, a_data['varvals'][dep], b_data['varvals'][dep]))
 
     changed, added, removed = dict_diff(a_data['file_checksum_values'], b_data['file_checksum_values'])
     if changed: