execfile should call PyErr_SetFromErrnoWithFilename instead of
simply PyErr_SetFromErrno

This closes bug 599163.
diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c
index 660abeb..2387deb 100644
--- a/Python/bltinmodule.c
+++ b/Python/bltinmodule.c
@@ -553,7 +553,7 @@
         }
 
 	if (!exists) {
-		PyErr_SetFromErrno(PyExc_IOError);
+		PyErr_SetFromErrnoWithFilename(PyExc_IOError, filename);
 		return NULL;
 	}
 	cf.cf_flags = 0;