diff --git a/src/bif_functions.c b/src/bif_functions.c
index 098f1d1a..24caba42 100644
--- a/src/bif_functions.c
+++ b/src/bif_functions.c
@@ -23,7 +23,7 @@
 	} \
 	if (errno == ENOMEM)										\
 		return throw_error(q, &p1, q->st.curr_frame, "resource_error", "memory"); \
-	q->accum.flags = (FLAG_MANAGED | FLAG_INT_BIG);								\
+	q->accum.flags = FLAG_INT_BIG | FLAG_MANAGED;								\
 	q->accum.val_bigint->refcnt = 0;							\
 }
 
@@ -39,7 +39,7 @@
 	} \
 	if (errno == ENOMEM)										\
 		return throw_error(q, p1, q->st.curr_frame, "resource_error", "memory"); \
-	q->accum.flags = (FLAG_MANAGED | FLAG_INT_BIG);								\
+	q->accum.flags = FLAG_INT_BIG | FLAG_MANAGED;								\
 	q->accum.val_bigint->refcnt = 0;							\
 }
 
@@ -54,7 +54,7 @@
 		if (mp_rat_init_copy(&q->accum.val_bigint->irat, &q->tmp_irat) == MP_MEMORY) {\
 			return throw_error(q, &p1, q->st.curr_frame, "resource_error", "memory"); \
 		} \
-		q->accum.flags = (FLAG_MANAGED | FLAG_INT_BIG);								\
+		q->accum.flags = FLAG_INT_BIG | FLAG_MANAGED;								\
 		q->accum.val_bigint->refcnt = 0;							\
 	} else { \
 		q->accum.tag = TAG_INTEGER;										\
@@ -64,7 +64,7 @@
 		if (mp_int_init_copy(&q->accum.val_bigint->ival, &q->tmp_irat.num) == MP_MEMORY) {\
 			return throw_error(q, &p1, q->st.curr_frame, "resource_error", "memory"); \
 		} \
-		q->accum.flags = (FLAG_MANAGED | FLAG_INT_BIG);								\
+		q->accum.flags = FLAG_INT_BIG | FLAG_MANAGED;								\
 		q->accum.val_bigint->refcnt = 0;							\
 	} \
 	if (errno == ENOMEM)										\
@@ -512,7 +512,7 @@ static bool bif_numerator_1(query *q)
 	mp_int_init_copy(&q->accum.val_bigint->ival, &p1.val_bigint->irat.num);
 	if (errno == ENOMEM)
 		return throw_error(q, &p1, q->st.curr_frame, "resource_error", "memory");
-	q->accum.flags = (FLAG_MANAGED | FLAG_INT_BIG);
+	q->accum.flags = FLAG_INT_BIG | FLAG_MANAGED;
 	q->accum.val_bigint->refcnt = 0;
 	return true;
 }
@@ -540,7 +540,7 @@ static bool bif_denominator_1(query *q)
 	mp_int_init_copy(&q->accum.val_bigint->ival, &p1.val_bigint->irat.den);
 	if (errno == ENOMEM)
 		return throw_error(q, &p1, q->st.curr_frame, "resource_error", "memory");
-	q->accum.flags = (FLAG_MANAGED | FLAG_INT_BIG);
+	q->accum.flags = FLAG_INT_BIG | FLAG_MANAGED;
 	q->accum.val_bigint->refcnt = 0;
 	return true;
 }
diff --git a/src/bif_predicates.c b/src/bif_predicates.c
index d1052732..9405b4b2 100644
--- a/src/bif_predicates.c
+++ b/src/bif_predicates.c
@@ -4761,7 +4761,7 @@ static bool bif_hex_chars_2(query *q)
 		check_heap_error(tmp.val_bigint);
 		tmp.val_bigint->refcnt = 1;
 		mp_int_init_copy(&tmp.val_bigint->ival, &v2);
-		tmp.flags |= ((FLAG_MANAGED | FLAG_INT_BIG) | FLAG_INT_BIG);
+		tmp.flags |= FLAG_INT_BIG | FLAG_MANAGED | FLAG_INT_BIG;
 	} else {
 		make_uint(&tmp, (unsigned long long)val);
 	}
@@ -4816,7 +4816,7 @@ static bool bif_octal_chars_2(query *q)
 		check_heap_error(tmp.val_bigint);
 		tmp.val_bigint->refcnt = 1;
 		mp_int_init_copy(&tmp.val_bigint->ival, &v2);
-		tmp.flags |= (FLAG_MANAGED | FLAG_INT_BIG);
+		tmp.flags |= FLAG_INT_BIG | FLAG_MANAGED;
 	} else {
 		make_uint(&tmp, (unsigned long long)val);
 	}
diff --git a/src/parser.c b/src/parser.c
index 17f6817f..17417703 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -2606,7 +2606,7 @@ static bool parse_number(parser *p, const char **srcptr, bool neg)
 			p->v.val_bigint->refcnt = 1;
 			mp_int_init_copy(&p->v.val_bigint->ival, &v2);
 			if (neg) p->v.val_bigint->ival.sign = MP_NEG;
-			p->v.flags |= FLAG_INT_BIG;
+			p->v.flags |= FLAG_INT_BIG | FLAG_MANAGED;
 		} else {
 			set_smallint(&p->v, val);
 			if (neg) p->v.val_int = -p->v.val_int;
@@ -2629,7 +2629,7 @@ static bool parse_number(parser *p, const char **srcptr, bool neg)
 			p->v.val_bigint->refcnt = 1;
 			mp_int_init_copy(&p->v.val_bigint->ival, &v2);
 			if (neg) p->v.val_bigint->ival.sign = MP_NEG;
-			p->v.flags |= FLAG_INT_BIG;
+			p->v.flags |= FLAG_INT_BIG | FLAG_MANAGED;
 		} else {
 			set_smallint(&p->v, val);
 			if (neg) p->v.val_int = -p->v.val_int;
@@ -2652,7 +2652,7 @@ static bool parse_number(parser *p, const char **srcptr, bool neg)
 			p->v.val_bigint->refcnt = 1;
 			mp_int_init_copy(&p->v.val_bigint->ival, &v2);
 			if (neg) p->v.val_bigint->ival.sign = MP_NEG;
-			p->v.flags |= FLAG_INT_BIG;
+			p->v.flags |= FLAG_INT_BIG | FLAG_MANAGED;
 		} else {
 			set_smallint(&p->v, val);
 			if (neg) p->v.val_int = -p->v.val_int;
@@ -2712,7 +2712,7 @@ static bool parse_number(parser *p, const char **srcptr, bool neg)
 		p->v.val_bigint->refcnt = 1;
 		mp_int_init_copy(&p->v.val_bigint->ival, &v2);
 		if (neg) p->v.val_bigint->ival.sign = MP_NEG;
-		p->v.flags |= FLAG_INT_BIG;
+		p->v.flags |= FLAG_INT_BIG | FLAG_MANAGED;
 	} else {
 		set_smallint(&p->v, val);
 		if (neg) p->v.val_int = -p->v.val_int;
diff --git a/src/query.c b/src/query.c
index c3245e7d..625605ad 100644
--- a/src/query.c
+++ b/src/query.c
@@ -1813,6 +1813,16 @@ void query_destroy(query *q)
 		free(save);
 	}
 
+	while (q->st.tp > 0) {
+		const trail *tr = q->trails + --q->st.tp;
+		const frame *f = GET_FRAME(tr->var_ctx);
+		slot *e = GET_SLOT(f, tr->var_nbr);
+		cell *c = &e->c;
+		unshare_cell(c);
+		c->tag = TAG_EMPTY;
+		c->attrs = tr->attrs;
+	}
+
 	for (int i = 0; i < MAX_QUEUES; i++)
 		free(q->queue[i]);