Bug fix: should check _mi_new() return value.

myisam/rt_split.c

@@ -330,8 +330,11 @@ int rtree_split_page(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *page, uchar *key,
   mi_putint(page, 2 + n1 * full_length, nod_flag);
   mi_putint(new_page, 2 + n2 * full_length, nod_flag);
 
-  *new_page_offs=_mi_new(info, keyinfo);
-  err_code= _mi_write_keypage(info, keyinfo, *new_page_offs, new_page);
+  if ((*new_page_offs= _mi_new(info, keyinfo)) == HA_OFFSET_ERROR)
+    err_code= -1;
+  else
+    err_code= _mi_write_keypage(info, keyinfo, *new_page_offs, new_page);
+
   my_afree((byte*)new_page);
 
 split_err: