diff --git a/contrib/patchbomb b/contrib/patchbomb
--- a/contrib/patchbomb
+++ b/contrib/patchbomb
@@ -107,6 +107,7 @@ def patchbomb(ui, repo, *revs, **opts):
     def makepatch(patch, idx, total):
         desc = []
         node = None
+        body = ''
         for line in patch:
             if line.startswith('#'):
                 if line.startswith('# Node ID'): node = line.split()[-1]