[gnome-builder] rg: fix some compiler warnings

[Christian Hergert <chergert src gnome org>]

commit 9bfa96eddee3d8a01da5132676a7a7e687f70e44
Author: Christian Hergert <christian hergert me>
Date:   Mon Jun 1 17:00:44 2015 -0700

    rg: fix some compiler warnings

 contrib/rg/rg-ring.c  |    6 +++---
 contrib/rg/rg-table.c |   16 ++++++++--------
 2 files changed, 11 insertions(+), 11 deletions(-)
---
diff --git a/contrib/rg/rg-ring.c b/contrib/rg/rg-ring.c
index 16a3a7d..feb5577 100644
--- a/contrib/rg/rg-ring.c
+++ b/contrib/rg/rg-ring.c
@@ -88,9 +88,9 @@ rg_ring_append_vals (RgRing        *ring,
   gint x;
   gint i;
 
-  g_return_if_fail (ring_impl != NULL);
-  g_return_if_fail (len <= ring->len);
-  g_return_if_fail (len > 0);
+  g_return_val_if_fail (ring_impl != NULL, 0);
+  g_return_val_if_fail (len <= ring->len, 0);
+  g_return_val_if_fail (len > 0, 0);
 
   for (i = 0; i < len; i++)
     {
diff --git a/contrib/rg/rg-table.c b/contrib/rg/rg-table.c
index b99314e..5f44089 100644
--- a/contrib/rg/rg-table.c
+++ b/contrib/rg/rg-table.c
@@ -127,8 +127,8 @@ rg_table_add_column (RgTable  *self,
 {
   RgTablePrivate *priv = rg_table_get_instance_private (self);
 
-  g_return_if_fail (RG_IS_TABLE (self));
-  g_return_if_fail (RG_IS_COLUMN (column));
+  g_return_val_if_fail (RG_IS_TABLE (self), 0);
+  g_return_val_if_fail (RG_IS_COLUMN (column), 0);
 
   _rg_column_set_n_rows (column, priv->max_samples);
 
@@ -216,9 +216,9 @@ rg_table_get_iter_last (RgTable     *self,
   RgTablePrivate *priv = rg_table_get_instance_private (self);
   RgTableIterImpl *impl = (RgTableIterImpl *)iter;
 
-  g_return_if_fail (RG_IS_TABLE (self));
-  g_return_if_fail (iter != NULL);
-  g_return_if_fail (impl != NULL);
+  g_return_val_if_fail (RG_IS_TABLE (self), FALSE);
+  g_return_val_if_fail (iter != NULL, FALSE);
+  g_return_val_if_fail (impl != NULL, FALSE);
 
   impl->table = self;
   impl->index = priv->last_index;
@@ -249,9 +249,9 @@ rg_table_get_iter_first (RgTable     *self,
   RgTablePrivate *priv = rg_table_get_instance_private (self);
   RgTableIterImpl *impl = (RgTableIterImpl *)iter;
 
-  g_return_if_fail (RG_IS_TABLE (self));
-  g_return_if_fail (iter != NULL);
-  g_return_if_fail (impl != NULL);
+  g_return_val_if_fail (RG_IS_TABLE (self), FALSE);
+  g_return_val_if_fail (iter != NULL, FALSE);
+  g_return_val_if_fail (impl != NULL, FALSE);
 
   impl->table = self;
   impl->index = (priv->last_index + 1) % priv->max_samples;