From: Victor Stinner <vstinner@python.org>
Date: Wed, 7 Apr 2021 21:12:45 +0000 (+0200)
Subject: bpo-42923: Fix _Py_DumpExtensionModules() for NULL sysdict (GH-25262)
X-Git-Tag: v3.10.0b1~370
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=3d55aa9e7365af76e40680271328deece27a7339;p=thirdparty%2FPython%2Fcpython.git

bpo-42923: Fix _Py_DumpExtensionModules() for NULL sysdict (GH-25262)

Fix Py_FatalError() is called before interp->sysdict is set.
---

diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c
index 64723ce82d76..0ad1796e3cbc 100644
--- a/Python/pylifecycle.c
+++ b/Python/pylifecycle.c
@@ -2551,12 +2551,14 @@ _Py_DumpExtensionModules(int fd, PyInterpreterState *interp)
     // memory cannot be allocated on the heap in a signal handler.
     // Iterate on the dict instead.
     PyObject *stdlib_module_names = NULL;
-    pos = 0;
-    while (PyDict_Next(interp->sysdict, &pos, &key, &value)) {
-        if (PyUnicode_Check(key)
-           && PyUnicode_CompareWithASCIIString(key, "stdlib_module_names") == 0) {
-            stdlib_module_names = value;
-            break;
+    if (interp->sysdict != NULL) {
+        pos = 0;
+        while (PyDict_Next(interp->sysdict, &pos, &key, &value)) {
+            if (PyUnicode_Check(key)
+               && PyUnicode_CompareWithASCIIString(key, "stdlib_module_names") == 0) {
+                stdlib_module_names = value;
+                break;
+            }
         }
     }
     // If we failed to get sys.stdlib_module_names or it's not a frozenset,