From 761fcd03aa71d16225850a797f6a7c67c12800ed Mon Sep 17 00:00:00 2001
From: Guido van Rossum <guido@python.org>
Date: Mon, 12 Apr 1999 22:51:20 +0000
Subject: [PATCH] Fix accidentally reversed NULL test in load_mark(). 
 Suggested by Tamito Kajiyama.  (This caused a bug only on platforms where
 malloc(0) returns NULL.)

---
 Modules/cPickle.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Modules/cPickle.c b/Modules/cPickle.c
index 614ff06c259..a661c660b04 100644
--- a/Modules/cPickle.c
+++ b/Modules/cPickle.c
@@ -3295,7 +3295,7 @@ load_mark(Unpicklerobject *self) {
     if ((self->num_marks + 1) >= self->marks_size) {
         s=self->marks_size+20;
         if (s <= self->num_marks) s=self->num_marks + 1;
-        if (self->marks)
+        if (self->marks == NULL)
             self->marks=(int *)malloc(s * sizeof(int));
         else
             self->marks=(int *)realloc(self->marks, s * sizeof(int));