From 7ce57d67c925be894486ff6e3a6e330a1986cdcd Mon Sep 17 00:00:00 2001
From: Christian Heimes <christian@cheimes.de>
Date: Thu, 11 Jul 2013 13:02:30 +0200
Subject: [PATCH] Issue #18426: improve exception message. Courtesy of Amaury

---
 Python/importdl.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/Python/importdl.c b/Python/importdl.c
index e393de153ba..0ea954cae0a 100644
--- a/Python/importdl.c
+++ b/Python/importdl.c
@@ -97,8 +97,12 @@ _PyImport_LoadDynamicModule(PyObject *name, PyObject *path, FILE *fp)
 
     /* Remember pointer to module init function. */
     def = PyModule_GetDef(m);
-    if (def == NULL)
+    if (def == NULL) {
+        PyErr_Format(PyExc_SystemError,
+                     "initialization of %s did not return an extension "
+                     "module", shortname);
         goto error;
+    }
     def->m_base.m_init = p;
 
     /* Remember the filename as the __file__ attribute */