- * Expands to the GNU C <literal>unused</literal> function attribute if
- * the compiler is <command>gcc</command>. It is used for declaring
- * functions which may never be used. It avoids possible compiler warnings.
- * See the GNU C documentation for details.
+ * Expands to the GNU C unused function attribute if the compiler is gcc.
+ * It is used for declaring functions and arguments which may never be used.
+ * It avoids possible compiler warnings.
+ *
+ * For functions, place the attribute after the declaration, just before the
+ * semicolon. For arguments, place the attribute at the beginning of the
+ * argument declaration.
+ *
+ * |[<!-- language="C" -->
+ * void my_unused_function (G_GNUC_UNUSED gint unused_argument,
+ * gint other_argument) G_GNUC_UNUSED;
+ * ]|
+ *
+ * See the GNU C documentation for more details.