factor: avoid compilation failure without libgmp

* src/factor.c (debug) [!HAVE_GMP]: Define.
Reported by Bob Proulx.

diff --git a/src/factor.c b/src/factor.c
index 8ccefd5..187143a 100644 (file)
--- a/src/factor.c
+++ b/src/factor.c
@@ -257,6 +257,14 @@ S4:
   mpz_clear (x);
   mpz_clear (y);
 }
+
+#else
+
+static void
+debug (char const *fmt ATTRIBUTE_UNUSED, ...)
+{
+}
+
 #endif
 
 /* The maximum number of factors, including -1, for negative numbers.  */