From ca7d9f42b3d159d01123492f87b2249a0053567c Mon Sep 17 00:00:00 2001
From: antirez <antirez@gmail.com>
Date: Fri, 15 Aug 2014 15:48:15 +0200
Subject: [PATCH] Fix undefined behavior in ll2string().

The bug was found by @CAFxX, thanks!
See issue #1940.
---
 src/util.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/util.c b/src/util.c
index a0bb2b84c..1b1798658 100644
--- a/src/util.c
+++ b/src/util.c
@@ -261,7 +261,11 @@ int ll2string(char* dst, size_t dstlen, long long svalue) {
     /* The main loop works with 64bit unsigned integers for simplicity, so
      * we convert the number here and remember if it is negative. */
     if (svalue < 0) {
-        value = -svalue;
+        if (svalue != LLONG_MIN) {
+            value = -svalue;
+        } else {
+            value = ((unsigned long long) LLONG_MAX)+1;
+        }
         negative = 1;
     } else {
         value = svalue;