From: Chandler Carruth <chandlerc@gmail.com>
Date: Tue, 4 Aug 2015 00:53:01 +0000 (+0000)
Subject: [UB] Fix another place where we would pass a null pointer to memcpy.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=d86ea348636c2368029034561d5c2e3f0c8a2f75;p=oota-llvm.git

[UB] Fix another place where we would pass a null pointer to memcpy.

This too was found by UBSan. Down to 35 failures for me.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243932 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/llvm/ADT/StringMap.h b/include/llvm/ADT/StringMap.h
index 8721c73b95b..9d038560bf9 100644
--- a/include/llvm/ADT/StringMap.h
+++ b/include/llvm/ADT/StringMap.h
@@ -158,7 +158,8 @@ public:
 
     // Copy the string information.
     char *StrBuffer = const_cast<char*>(NewItem->getKeyData());
-    memcpy(StrBuffer, Key.data(), KeyLength);
+    if (KeyLength > 0)
+      memcpy(StrBuffer, Key.data(), KeyLength);
     StrBuffer[KeyLength] = 0;  // Null terminate for convenience of clients.
     return NewItem;
   }