# HG changeset patch
# User Augie Fackler <augie@google.com>
# Date 2018-10-08 15:42:06
# Node ID 129bfc7ad2ccac6775041ec7751d67b01f57c8cd
# Parent  1d09ba0d2ed3d19f1ca1b116591cc413eb87ac65

revlog: if the module is initialized more than once, don't leak nullentry

Caught (annoyingly) by the manifest fuzzer.

Differential Revision: https://phab.mercurial-scm.org/D4905

diff --git a/mercurial/cext/revlog.c b/mercurial/cext/revlog.c
--- a/mercurial/cext/revlog.c
+++ b/mercurial/cext/revlog.c
@@ -2304,8 +2304,10 @@ void revlog_module_init(PyObject *mod)
 	Py_INCREF(&nodetreeType);
 	PyModule_AddObject(mod, "nodetree", (PyObject *)&nodetreeType);
 
-	nullentry = Py_BuildValue(PY23("iiiiiiis#", "iiiiiiiy#"), 0, 0, 0,
-				  -1, -1, -1, -1, nullid, 20);
+	if (!nullentry) {
+		nullentry = Py_BuildValue(PY23("iiiiiiis#", "iiiiiiiy#"), 0, 0, 0,
+					  -1, -1, -1, -1, nullid, 20);
+	}
 	if (nullentry)
 		PyObject_GC_UnTrack(nullentry);
 }