+#if defined STANDALONE_SOLVER && defined __GNUC__
+/*
+ * Forward-declare the functions taking printf-like format arguments
+ * with __attribute__((format)) so as to ensure the argument syntax
+ * gets debugged.
+ */
+struct solver_scratch;
+static int solver_elim(struct solver_usage *usage, int *indices,
+ char *fmt, ...) __attribute__((format(printf,3,4)));
+static int solver_intersect(struct solver_usage *usage,
+ int *indices1, int *indices2, char *fmt, ...)
+ __attribute__((format(printf,4,5)));
+static int solver_set(struct solver_usage *usage,
+ struct solver_scratch *scratch,
+ int *indices, char *fmt, ...)
+ __attribute__((format(printf,4,5)));
+#endif
+