fixes following cppcheck warnings

src/core/disk.c

@@ -75,7 +75,7 @@ static void add_async_event(struct _starpu_async_channel * channel, void * event
 
 int starpu_disk_register(struct starpu_disk_ops *func, void *parameter, starpu_ssize_t size)
 {
-	STARPU_ASSERT_MSG(size < 0 || size >= STARPU_DISK_SIZE_MIN,"Minimum disk size is %u Bytes ! (Here %u) \n", (int) STARPU_DISK_SIZE_MIN, (int) size);
+	STARPU_ASSERT_MSG(size < 0 || size >= STARPU_DISK_SIZE_MIN, "Minimum disk size is %d Bytes ! (Here %d) \n", (int) STARPU_DISK_SIZE_MIN, (int) size);
 	/* register disk */
 	unsigned memory_node = _starpu_memory_node_register(STARPU_DISK_RAM, 0);
 

src/datawizard/filters.c

@@ -139,7 +139,7 @@ starpu_data_handle_t fstarpu_data_get_sub_data(starpu_data_handle_t root_handle,
 		STARPU_ASSERT(next_child >= 0);
 
 		STARPU_ASSERT_MSG(current_handle->nchildren != 0, "Data %p has to be partitioned before accessing children", current_handle);
-		STARPU_ASSERT_MSG((unsigned) next_child < current_handle->nchildren, "Bogus child number %u, data %p only has %u children", next_child, current_handle, current_handle->nchildren);
+		STARPU_ASSERT_MSG((unsigned) next_child < current_handle->nchildren, "Bogus child number %d, data %p only has %u children", next_child, current_handle, current_handle->nchildren);
 
 		current_handle = &current_handle->children[next_child];
 	}