From: Jonathan Wakely <jwakely@redhat.com>
Date: Mon, 14 May 2018 22:35:44 +0000 (+0100)
Subject: PR libstdc++/67554 Do not pass null pointers to memcpy
X-Git-Tag: releases/gcc-6.5.0~322
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0eaf27ec4888d5052a5cbf4ab33c487339dc8069;p=thirdparty%2Fgcc.git

PR libstdc++/67554 Do not pass null pointers to memcpy

	PR libstdc++/67554
	* include/bits/valarray_array.h (_Array_copy_ctor<_Tp, true>)
	(_Array_copier<_Tp, true>): Do not pass null pointers to memcpy.

From-SVN: r260244
---

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index b003c5951e3c..6ecaada6df6a 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,9 @@
+2018-05-14  Jonathan Wakely  <jwakely@redhat.com>
+
+	PR libstdc++/67554
+	* include/bits/valarray_array.h (_Array_copy_ctor<_Tp, true>)
+	(_Array_copier<_Tp, true>): Do not pass null pointers to memcpy.
+
 2018-05-10  Jonathan Wakely  <jwakely@redhat.com>
 
 	* doc/xml/manual/debug_mode.xml: Add array and forward_list to list
diff --git a/libstdc++-v3/include/bits/valarray_array.h b/libstdc++-v3/include/bits/valarray_array.h
index d6f8e7a23fc6..4df1181600e9 100644
--- a/libstdc++-v3/include/bits/valarray_array.h
+++ b/libstdc++-v3/include/bits/valarray_array.h
@@ -152,7 +152,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     {
       inline static void
       _S_do_it(const _Tp* __b, const _Tp* __e, _Tp* __restrict__ __o)
-      { __builtin_memcpy(__o, __b, (__e - __b) * sizeof(_Tp)); }
+      {
+	if (__b)
+	  __builtin_memcpy(__o, __b, (__e - __b) * sizeof(_Tp));
+      }
     };
 
   template<typename _Tp>
@@ -258,7 +261,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     {
       inline static void
       _S_do_it(const _Tp* __restrict__ __a, size_t __n, _Tp* __restrict__ __b)
-      { __builtin_memcpy(__b, __a, __n * sizeof (_Tp)); }
+      {
+	if (__n != 0)
+	  __builtin_memcpy(__b, __a, __n * sizeof (_Tp));
+      }
     };
 
   // Copy a plain array __a[<__n>] into a play array __b[<>]