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diff --git a/gdb/common/poison.h b/gdb/common/poison.h
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+/* Poison symbols at compile time.
+
+   Copyright (C) 2017 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#ifndef COMMON_POISON_H
+#define COMMON_POISON_H
+
+#include "traits.h"
+
+/* Poison memset of non-POD types.  The idea is catching invalid
+   initialization of non-POD structs that is easy to be introduced as
+   side effect of refactoring.  For example, say this:
+
+ struct S { VEC(foo_s) *m_data; };
+
+is converted to this at some point:
+
+ struct S {
+   S() { m_data.reserve (10); }
+   std::vector<foo> m_data;
+ };
+
+and old code was initializing S objects like this:
+
+ struct S s;
+ memset (&s, 0, sizeof (S)); // whoops, now wipes vector.
+
+Declaring memset as deleted for non-POD types makes the memset above
+be a compile-time error.  */
+
+/* Helper for SFINAE.  True if "T *" is memsettable.  I.e., if T is
+   either void, or POD.  */
+template<typename T>
+struct IsMemsettable
+  : gdb::Or<std::is_void<T>,
+	    std::is_pod<T>>
+{};
+
+template <typename T,
+	  typename = gdb::Requires<gdb::Not<IsMemsettable<T>>>>
+void *memset (T *s, int c, size_t n) = delete;
+
+/* Similarly, poison memcpy and memmove of non trivially-copyable
+   types, which is undefined.  */
+
+/* True if "T *" is relocatable.  I.e., copyable with memcpy/memmove.
+   I.e., T is either trivially copyable, or void.  */
+template<typename T>
+struct IsRelocatable
+  : gdb::Or<std::is_void<T>,
+	    std::is_trivially_copyable<T>>
+{};
+
+/* True if both source and destination are relocatable.  */
+
+template <typename D, typename S>
+using BothAreRelocatable
+  = gdb::And<IsRelocatable<D>, IsRelocatable<S>>;
+
+template <typename D, typename S,
+	  typename = gdb::Requires<gdb::Not<BothAreRelocatable<D, S>>>>
+void *memcpy (D *dest, const S *src, size_t n) = delete;
+
+template <typename D, typename S,
+	  typename = gdb::Requires<gdb::Not<BothAreRelocatable<D, S>>>>
+void *memmove (D *dest, const S *src, size_t n) = delete;
+
+#endif /* COMMON_POISON_H */