Fixed #1254: pdb fails to launch some script.
diff --git a/Lib/pdb.py b/Lib/pdb.py
index f355d45..d4eb8bd 100755
--- a/Lib/pdb.py
+++ b/Lib/pdb.py
@@ -1123,7 +1123,7 @@
# Start with fresh empty copy of globals and locals and tell the script
# that it's being run as __main__ to avoid scripts being able to access
# the pdb.py namespace.
- globals_ = {"__name__" : "__main__"}
+ globals_ = {"__name__" : "__main__", "__file__" : filename}
locals_ = globals_
# When bdb sets tracing, a number of call and line events happens