+/* Attribute 'nonstring' was valid as of gcc 8. */
+#ifndef ATTRIBUTE_NONSTRING
+# if GCC_VERSION >= 8000
+# define ATTRIBUTE_NONSTRING __attribute__ ((__nonstring__))
+# else
+# define ATTRIBUTE_NONSTRING
+# endif
+#endif
+
+/* Attribute `alloc_size' was valid as of gcc 4.3. */
+#ifndef ATTRIBUTE_RESULT_SIZE_1
+# if (GCC_VERSION >= 4003)
+# define ATTRIBUTE_RESULT_SIZE_1 __attribute__ ((alloc_size (1)))
+# else
+# define ATTRIBUTE_RESULT_SIZE_1
+#endif
+#endif
+
+#ifndef ATTRIBUTE_RESULT_SIZE_2
+# if (GCC_VERSION >= 4003)
+# define ATTRIBUTE_RESULT_SIZE_2 __attribute__ ((alloc_size (2)))
+# else
+# define ATTRIBUTE_RESULT_SIZE_2
+#endif
+#endif
+
+#ifndef ATTRIBUTE_RESULT_SIZE_1_2
+# if (GCC_VERSION >= 4003)
+# define ATTRIBUTE_RESULT_SIZE_1_2 __attribute__ ((alloc_size (1, 2)))
+# else
+# define ATTRIBUTE_RESULT_SIZE_1_2
+#endif
+#endif
+
+/* Attribute `warn_unused_result' was valid as of gcc 3.3. */
+#ifndef ATTRIBUTE_WARN_UNUSED_RESULT
+# if GCC_VERSION >= 3003
+# define ATTRIBUTE_WARN_UNUSED_RESULT __attribute__ ((warn_unused_result))
+# else
+# define ATTRIBUTE_WARN_UNUSED_RESULT
+# endif
+#endif
+