From 51f5a1a8fee29bd2414b8799f3120cc0746ed906 Mon Sep 17 00:00:00 2001
From: Rafael Espindola <rafael.espindola@gmail.com>
Date: Tue, 7 Jul 2015 19:00:02 +0000
Subject: [PATCH] Don't pass a null pointer to memcpy.

Fixes pr23650.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241617 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/Support/raw_ostream.h | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/include/llvm/Support/raw_ostream.h b/include/llvm/Support/raw_ostream.h
index b59317112c4..28e512c8694 100644
--- a/include/llvm/Support/raw_ostream.h
+++ b/include/llvm/Support/raw_ostream.h
@@ -165,8 +165,10 @@ public:
     if (Size > (size_t)(OutBufEnd - OutBufCur))
       return write(Str.data(), Size);
 
-    memcpy(OutBufCur, Str.data(), Size);
-    OutBufCur += Size;
+    if (Size) {
+      memcpy(OutBufCur, Str.data(), Size);
+      OutBufCur += Size;
+    }
     return *this;
   }