commit c7f165fe652651c32833245fc902c790a4f173fa
author Oren Milman <orenmn@gmail.com> Fri Sep 15 10:20:11 2017 +0300
committer Serhiy Storchaka <storchaka@gmail.com> Fri Sep 15 10:20:11 2017 +0300
tree 8082204f2fca451d16ffba87e18c18562f69d8c0
parent a72d15c97f9837f6c9c6bd476a62175c942cc588

[2.7] bpo-31471: Fix assertion failure in subprocess.Popen() on Windows, in case env has a bad keys() method. (GH-3580) (#3595)

PC/_subprocess.c

diff --git a/PC/_subprocess.c b/PC/_subprocess.c
index f73d14f..fc9aaa4 100644
--- a/PC/_subprocess.c
+++ b/PC/_subprocess.c
@@ -341,9 +341,13 @@
     envsize = PyMapping_Length(environment);
 
     keys = PyMapping_Keys(environment);
+    if (!keys) {
+        return NULL;
+    }
     values = PyMapping_Values(environment);
-    if (!keys || !values)
+    if (!values) {
         goto error;
+    }
 
     out = PyString_FromStringAndSize(NULL, 2048);
     if (! out)