diff --git a/lib/bb/checksum.py b/lib/bb/checksum.py
index 557793d3..5294ddf1 100644
--- a/lib/bb/checksum.py
+++ b/lib/bb/checksum.py
@@ -140,5 +140,5 @@ class FileChecksumCache(MultiProcessCache):
                 if checksum:
                     checksums.append((pth, checksum))
 
-        checksums.sort(key=operator.itemgetter(1))
+        checksums.sort(key=lambda x:(x[1], x[0]))
         return checksums