+#ifdef HAVE_ATTR_PACKED
+#define PACKED(...) __VA_ARGS__ __attribute__((__packed__))
+#else
+#ifdef _MSC_VER
+#define PACKED(...) __pragma(pack(push, 1)) __VA_ARGS__ __pragma(pack(pop))
+#else
+#warning Your compiler does not support __packed__. Use at your own risk.
+#endif
+#endif
+
+#if defined(HAVE_ATTR_MALLOC_WITH_ARG)
+#define ATTR_DEALLOCATOR(dealloc) __attribute__((__malloc__(dealloc)))
+#else
+#define ATTR_DEALLOCATOR(dealloc)
+#endif
+
+#ifdef HAVE_ATTR_MALLOC
+#define ATTR_MALLOC __attribute__((__malloc__))
+#else
+#define ATTR_MALLOC
+#endif
+
+#ifdef HAVE_ATTR_NONNULL
+#define ATTR_NONNULL __attribute__((__nonnull__))
+#else
+#define ATTR_NONNULL
+#endif
+
+#ifdef HAVE_ATTR_WARN_UNUSED_RESULT
+#define ATTR_WARN_UNUSED __attribute__((__warn_unused_result__))
+#else
+#define ATTR_WARN_UNUSED
+#endif
+
+#ifdef HAVE_ATTR_FORMAT
+#define ATTR_FORMAT(func, str, nonstr) __attribute__((format(func, str, nonstr)))
+#else
+#define ATTR_FORMAT(func, str, nonstr)
+#endif
+