+ else
+ {
+ /* With a simpler 'if (no)' version, -Werror means -Werror=all
+ (or rather, -Werror=no-none, but that syntax is invalid).
+ The difference is:
+ - Werror activates all errors, but not the warnings
+ - Werror=all activates errors, and all warnings */
+ if (no ? !err : err)
+ *flags |= all;
+ else
+ *flags &= ~all;
+ }
+}
+/** Decode an option's set of keys.
+ *
+ * \param option option being decoded.
+ * \param keys array of valid subarguments.
+ * \param values array of corresponding (int) values.
+ * \param all the all value.
+ * \param flags the flags to update
+ * \param args comma separated list of effective subarguments to decode.
+ * If 0, then activate all the flags.
+ */
+static void
+flags_argmatch (const char *option,
+ const char * const keys[], const int values[],
+ int all, int *flags, char *args)
+{
+ if (args)
+ for (args = strtok (args, ","); args; args = strtok (NULL, ","))
+ {
+ size_t no = STRPREFIX_LIT ("no-", args) ? 3 : 0;
+ size_t err = STRPREFIX_LIT ("error", args + no) ? 5 : 0;
+
+ flag_argmatch (option, keys,
+ values, all, err ? &errors_flag : flags,
+ args, no, err);
+ }