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diff --git a/src/util/Cast.hxx b/src/util/Cast.hxx
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--- /dev/null
+++ b/src/util/Cast.hxx
@@ -0,0 +1,109 @@
+/*
+ * Copyright (C) 2013-2014 Max Kellermann <max@duempel.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
+ * FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef CAST_HXX
+#define CAST_HXX
+
+#include "Compiler.h"
+
+#include <stddef.h>
+
+/**
+ * Offset the given pointer by the specified number of bytes.
+ */
+static inline constexpr void *
+OffsetPointer(void *p, ptrdiff_t offset)
+{
+	return (char *)p + offset;
+}
+
+/**
+ * Offset the given pointer by the specified number of bytes.
+ */
+static inline constexpr const void *
+OffsetPointer(const void *p, ptrdiff_t offset)
+{
+	return (const char *)p + offset;
+}
+
+template<typename T, typename U>
+static inline constexpr T *
+OffsetCast(U *p, ptrdiff_t offset)
+{
+	return reinterpret_cast<T *>(OffsetPointer(p, offset));
+}
+
+template<typename T, typename U>
+static inline constexpr T *
+OffsetCast(const U *p, ptrdiff_t offset)
+{
+	return reinterpret_cast<const T *>(OffsetPointer(p, offset));
+}
+
+template<class C, class A>
+static constexpr inline ptrdiff_t
+ContainerAttributeOffset(const C *null_c, const A C::*p)
+{
+	return ptrdiff_t((const char *)null_c - (const char *)&(null_c->*p));
+}
+
+template<class C, class A>
+static constexpr inline ptrdiff_t
+ContainerAttributeOffset(const A C::*p)
+{
+	return ContainerAttributeOffset<C, A>(nullptr, p);
+}
+
+/**
+ * Cast the given pointer to a struct member to its parent structure.
+ */
+template<class C, class A>
+#if defined(__clang__) || GCC_CHECK_VERSION(4,7)
+constexpr
+#endif
+static inline C &
+ContainerCast(A &a, A C::*member)
+{
+	return *OffsetCast<C, A>(&a, ContainerAttributeOffset<C, A>(member));
+}
+
+/**
+ * Cast the given pointer to a struct member to its parent structure.
+ */
+template<class C, class A>
+#if defined(__clang__) || GCC_CHECK_VERSION(4,7)
+constexpr
+#endif
+static inline const C &
+ContainerCast(const A &a, A C::*member)
+{
+	return *OffsetCast<const C, const A>(&a, ContainerAttributeOffset<C, A>(member));
+}
+
+#endif