- Wnone = 0, /**< Issue no warnings. */
- Wmidrule_values = 1 << 0, /**< Unset or unused midrule values. */
- Wyacc = 1 << 1, /**< POSIXME. */
- Wconflicts_sr = 1 << 2, /**< S/R conflicts. */
- Wconflicts_rr = 1 << 3, /**< R/R conflicts. */
- Wdeprecated = 1 << 4, /**< Obsolete constructs. */
- Wprecedence = 1 << 5, /**< Useless precedence and associativity. */
+ warning_midrule_values, /**< Unset or unused midrule values. */
+ warning_yacc, /**< POSIXME. */
+ warning_conflicts_sr, /**< S/R conflicts. */
+ warning_conflicts_rr, /**< R/R conflicts. */
+ warning_empty_rule, /**< Implicitly empty rules. */
+ warning_deprecated, /**< Obsolete constructs. */
+ warning_precedence, /**< Useless precedence and associativity. */
+ warning_other, /**< All other warnings. */
+
+ warnings_size /**< The number of warnings. Must be last. */
+ } warning_bit;
+
+/** Whether -Werror was set. */
+extern bool warnings_are_errors;
+
+/** Decode a single argument from -W.
+ *
+ * \param arg the subarguments to decode.
+ * If null, then activate all the flags.
+ * \param no length of the potential "no-" prefix.
+ * Can be 0 or 3. If 3, negate the action of the subargument.
+ * \param err length of a potential "error=".
+ * Can be 0 or 6. If 6, treat the subargument as a CATEGORY.
+ *
+ * If VALUE != 0 then KEY sets flags and no-KEY clears them.
+ * If VALUE == 0 then KEY clears all flags from \c all and no-KEY sets all
+ * flags from \c all. Thus no-none = all and no-all = none.
+ */
+void warning_argmatch (char const *arg, size_t no, size_t err);
+
+/** Decode a comma-separated list of arguments from -W.
+ *
+ * \param args comma separated list of effective subarguments to decode.
+ * If 0, then activate all the flags.
+ */
+void warnings_argmatch (char *args);
+
+
+/*-----------.
+| complain. |
+`-----------*/
+
+/** Initialize this module. */
+void complain_init (void);