diff --git a/zephyr/lib/unminify.py b/zephyr/lib/unminify.py
index 942a2f7b3e..31bd1d4397 100644
--- a/zephyr/lib/unminify.py
+++ b/zephyr/lib/unminify.py
@@ -38,7 +38,7 @@ class SourceMap(object):
                     out += ('       = %s line %d column %d\n' %
                         (result.src, result.src_line+1, result.src_col+1))
                 except IndexError:
-                    out +=  '       [Unable to look up in source map]'
+                    out +=  '       [Unable to look up in source map]\n'
 
             if ln.startswith('    at'):
                 out += '\n'