From 760e0a620d452db417c8fd2e853ab3425ecf1a3c Mon Sep 17 00:00:00 2001
From: Mark Wooding <mdw@distorted.org.uk>
Date: Sun, 24 Nov 2019 15:07:08 +0000
Subject: [PATCH] util.c (mkexc): Populate dictionary before constructing
 exception class.

It turns out that the dictionary contents are copied into the new class
rather than being used by reference, so populating it later doesn't
actually do anything.
---
 util.c | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/util.c b/util.c
index 9332c8b..29f7d12 100644
--- a/util.c
+++ b/util.c
@@ -324,13 +324,7 @@ PyObject *mkexc(PyObject *mod, PyObject *base,
   PyObject *func = 0;
   PyObject *meth = 0;
 
-  if ((nameobj = PyString_FromFormat("%s.%s",
-				     PyModule_GetName(mod),
-				     name)) == 0 ||
-      (dict = PyDict_New()) == 0 ||
-      (exc = PyErr_NewException(PyString_AS_STRING(nameobj),
-				base, dict)) == 0)
-    goto fail;
+  if ((dict = PyDict_New()) == 0) goto fail;
 
   if (mm) {
     while (mm->ml_name) {
@@ -344,6 +338,13 @@ PyObject *mkexc(PyObject *mod, PyObject *base,
     }
   }
 
+  if ((nameobj = PyString_FromFormat("%s.%s",
+				     PyModule_GetName(mod),
+				     name)) == 0 ||
+      (exc = PyErr_NewException(PyString_AS_STRING(nameobj),
+				base, dict)) == 0)
+    goto fail;
+
 done:
   Py_XDECREF(nameobj);
   Py_XDECREF(dict);
-- 
2.11.0