Index: sys/sys/qmath.h
===================================================================
--- sys/sys/qmath.h
+++ sys/sys/qmath.h
@@ -219,7 +219,8 @@
 	int _i;								\
 	if (Q_LTZ(q) && ((ptrdiff_t)(slen)) > 0)			\
 		*_s++ = '-';						\
-	Q_BT(q) _part = Q_GIABSVAL(q);					\
+	/* The "1 *" is to deconst the type. */				\
+	Q_BT(1 * q) _part = Q_GIABSVAL(q);				\
 	_r = _s;							\
 	do {								\
 		/* Render integer chars in reverse order. */		\