From: Lucian Grijincu <lucian@fb.com>
Date: Mon, 9 May 2016 19:16:40 +0000 (-0700)
Subject: folly: fbvector: ubsan: avoid memcpy(dest, nullptr, 0)
X-Git-Tag: 2016.07.26~263
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=d45588bd939f6303acea8061e86eedf4a901baa3;p=folly.git

folly: fbvector: ubsan: avoid memcpy(dest, nullptr, 0)

Reviewed By: meyering

Differential Revision: D3277138

fbshipit-source-id: 7050d18c256ac15c8122d4af59aa31208b1466fd
---

diff --git a/folly/FBVector.h b/folly/FBVector.h
index e1809f31..fb611e56 100644
--- a/folly/FBVector.h
+++ b/folly/FBVector.h
@@ -636,7 +636,9 @@ private:
   }
 
   void relocate_move_or_memcpy(T* dest, T* first, T* last, std::true_type) {
-    std::memcpy((void*)dest, (void*)first, (last - first) * sizeof(T));
+    if (first != nullptr) {
+      std::memcpy((void*)dest, (void*)first, (last - first) * sizeof(T));
+    }
   }
 
   void relocate_move_or_memcpy(T* dest, T* first, T* last, std::false_type) {