--- /dev/null
+/** @file
+ * IPRT - Compile Time Assertions.
+ */
+
+/*
+ * Copyright (C) 2006-2017 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ *
+ * The contents of this file may alternatively be used under the terms
+ * of the Common Development and Distribution License Version 1.0
+ * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
+ * VirtualBox OSE distribution, in which case the provisions of the
+ * CDDL are applicable instead of those of the GPL.
+ *
+ * You may elect to license modified versions of this file under the
+ * terms and conditions of either the GPL or the CDDL or both.
+ */
+
+#ifndef ___iprt_assertcompile_h
+#define ___iprt_assertcompile_h
+
+#include <iprt/cdefs.h>
+
+/** @defgroup grp_rt_assert_compile Compile time assertions
+ * @ingroup grp_rt
+ *
+ * These assertions are used to check structure sizes, member/size alignments
+ * and similar compile time expressions.
+ *
+ * @remarks As you might have noticed, the AssertCompile macros don't follow the
+ * coding guidelines wrt to macros supposedly being all uppercase and
+ * underscored. For various reasons they don't, and nobody has
+ * complained yet.
+ *
+ * @{
+ */
+
+/**
+ * RTASSERTTYPE is the type the AssertCompile() macro redefines.
+ * It has no other function and shouldn't be used.
+ * Visual C++ uses this.
+ */
+typedef int RTASSERTTYPE[1];
+
+/**
+ * RTASSERTVAR is the type the AssertCompile() macro redefines.
+ * It has no other function and shouldn't be used.
+ * GCC uses this.
+ */
+#ifdef __GNUC__
+RT_C_DECLS_BEGIN
+#endif
+extern int RTASSERTVAR[1];
+#ifdef __GNUC__
+RT_C_DECLS_END
+#endif
+
+/** @def RTASSERT_HAVE_STATIC_ASSERT
+ * Indicates that the compiler implements static_assert(expr, msg).
+ */
+#ifdef _MSC_VER
+# if _MSC_VER >= 1600 && defined(__cplusplus)
+# define RTASSERT_HAVE_STATIC_ASSERT
+# endif
+#endif
+#if defined(__GNUC__) && defined(__GXX_EXPERIMENTAL_CXX0X__)
+# define RTASSERT_HAVE_STATIC_ASSERT
+#endif
+#if RT_CLANG_PREREQ(6, 0)
+# if __has_feature(cxx_static_assert) || __has_feature(c_static_assert)
+# define RTASSERT_HAVE_STATIC_ASSERT
+# endif
+#endif
+#ifdef DOXYGEN_RUNNING
+# define RTASSERT_HAVE_STATIC_ASSERT
+#endif
+
+/** @def AssertCompileNS
+ * Asserts that a compile-time expression is true. If it's not break the build.
+ *
+ * This differs from AssertCompile in that it accepts some more expressions
+ * than what C++0x allows - NS = Non-standard.
+ *
+ * @param expr Expression which should be true.
+ */
+#ifdef __GNUC__
+# define AssertCompileNS(expr) extern int RTASSERTVAR[1] __attribute__((__unused__)), RTASSERTVAR[(expr) ? 1 : 0] __attribute__((__unused__))
+#elif defined(__IBMC__) || defined(__IBMCPP__)
+# define AssertCompileNS(expr) extern int RTASSERTVAR[(expr) ? 1 : 0]
+#else
+# define AssertCompileNS(expr) typedef int RTASSERTTYPE[(expr) ? 1 : 0]
+#endif
+
+/** @def AssertCompile
+ * Asserts that a C++0x compile-time expression is true. If it's not break the
+ * build.
+ * @param expr Expression which should be true.
+ */
+#ifdef RTASSERT_HAVE_STATIC_ASSERT
+# define AssertCompile(expr) static_assert(!!(expr), #expr)
+#else
+# define AssertCompile(expr) AssertCompileNS(expr)
+#endif
+
+/** @def RTASSERT_OFFSET_OF()
+ * A offsetof() macro suitable for compile time assertions.
+ * Both GCC v4 and VisualAge for C++ v3.08 has trouble using RT_OFFSETOF.
+ */
+#if defined(__GNUC__)
+# if __GNUC__ >= 4
+# define RTASSERT_OFFSET_OF(a_Type, a_Member) __builtin_offsetof(a_Type, a_Member)
+# else
+# define RTASSERT_OFFSET_OF(a_Type, a_Member) RT_OFFSETOF(a_Type, a_Member)
+# endif
+#elif (defined(__IBMC__) || defined(__IBMCPP__)) && defined(RT_OS_OS2)
+# define RTASSERT_OFFSET_OF(a_Type, a_Member) __offsetof(a_Type, a_Member)
+#elif (defined(__WATCOMC__) && defined(__cplusplus))
+# define RTASSERT_OFFSET_OF(a_Type, a_Member) __offsetof(a_Type, a_Member)
+#else
+# define RTASSERT_OFFSET_OF(a_Type, a_Member) RT_OFFSETOF(a_Type, a_Member)
+#endif
+
+
+/** @def AssertCompileSize
+ * Asserts a size at compile.
+ * @param type The type.
+ * @param size The expected type size.
+ */
+#define AssertCompileSize(type, size) \
+ AssertCompile(sizeof(type) == (size))
+
+/** @def AssertCompileSizeAlignment
+ * Asserts a size alignment at compile.
+ * @param type The type.
+ * @param align The size alignment to assert.
+ */
+#define AssertCompileSizeAlignment(type, align) \
+ AssertCompile(!(sizeof(type) & ((align) - 1)))
+
+/** @def AssertCompileMemberSize
+ * Asserts a member offset alignment at compile.
+ * @param type The type.
+ * @param member The member.
+ * @param size The member size to assert.
+ */
+#define AssertCompileMemberSize(type, member, size) \
+ AssertCompile(RT_SIZEOFMEMB(type, member) == (size))
+
+/** @def AssertCompileMemberSizeAlignment
+ * Asserts a member size alignment at compile.
+ * @param type The type.
+ * @param member The member.
+ * @param align The member size alignment to assert.
+ */
+#define AssertCompileMemberSizeAlignment(type, member, align) \
+ AssertCompile(!(RT_SIZEOFMEMB(type, member) & ((align) - 1)))
+
+/** @def AssertCompileMemberAlignment
+ * Asserts a member offset alignment at compile.
+ * @param type The type.
+ * @param member The member.
+ * @param align The member offset alignment to assert.
+ */
+#define AssertCompileMemberAlignment(type, member, align) \
+ AssertCompile(!(RTASSERT_OFFSET_OF(type, member) & ((align) - 1)))
+
+/** @def AssertCompileMemberOffset
+ * Asserts an offset of a structure member at compile.
+ * @param type The type.
+ * @param member The member.
+ * @param off The expected offset.
+ */
+#define AssertCompileMemberOffset(type, member, off) \
+ AssertCompile(RTASSERT_OFFSET_OF(type, member) == (off))
+
+/** @def AssertCompile2MemberOffsets
+ * Asserts that two (sub-structure) members in union have the same offset.
+ * @param type The type.
+ * @param member1 The first member.
+ * @param member2 The second member.
+ */
+#define AssertCompile2MemberOffsets(type, member1, member2) \
+ AssertCompile(RTASSERT_OFFSET_OF(type, member1) == RTASSERT_OFFSET_OF(type, member2))
+
+/** @def AssertCompileAdjacentMembers
+ * Asserts that two structure members are adjacent.
+ * @param type The type.
+ * @param member1 The first member.
+ * @param member2 The second member.
+ */
+#define AssertCompileAdjacentMembers(type, member1, member2) \
+ AssertCompile(RTASSERT_OFFSET_OF(type, member1) + RT_SIZEOFMEMB(type, member1) == RTASSERT_OFFSET_OF(type, member2))
+
+/** @def AssertCompileMembersAtSameOffset
+ * Asserts that members of two different structures are at the same offset.
+ * @param type1 The first type.
+ * @param member1 The first member.
+ * @param type2 The second type.
+ * @param member2 The second member.
+ */
+#define AssertCompileMembersAtSameOffset(type1, member1, type2, member2) \
+ AssertCompile(RTASSERT_OFFSET_OF(type1, member1) == RTASSERT_OFFSET_OF(type2, member2))
+
+/** @def AssertCompileMembersSameSize
+ * Asserts that members of two different structures have the same size.
+ * @param type1 The first type.
+ * @param member1 The first member.
+ * @param type2 The second type.
+ * @param member2 The second member.
+ */
+#define AssertCompileMembersSameSize(type1, member1, type2, member2) \
+ AssertCompile(RT_SIZEOFMEMB(type1, member1) == RT_SIZEOFMEMB(type2, member2))
+
+/** @def AssertCompileMembersSameSizeAndOffset
+ * Asserts that members of two different structures have the same size and are
+ * at the same offset.
+ * @param type1 The first type.
+ * @param member1 The first member.
+ * @param type2 The second type.
+ * @param member2 The second member.
+ */
+#define AssertCompileMembersSameSizeAndOffset(type1, member1, type2, member2) \
+ AssertCompile( RTASSERT_OFFSET_OF(type1, member1) == RTASSERT_OFFSET_OF(type2, member2) \
+ && RT_SIZEOFMEMB(type1, member1) == RT_SIZEOFMEMB(type2, member2))
+
+/** @} */
+
+#endif
+
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