[build] Fix compiler warnings on some gcc versions

xfer_buffer() uses intf_get_dest_op() to obtain the destination interface for xfer_deliver(), in order to check that this is the same interface which provides xfer_buffer(). The return value from intf_get_dest_op() (which contains the actual method implementing xfer_deliver()) is not used. On some gcc versions, this triggers a "value computed is not used" warning, since the explicit type cast included within the intf_get_dest_op() macro is treated as a "value computed". Fix by explicitly casting the result of intf_get_dest_op() to void. Reported-by: Matthew Helton <mwhelton@gmail.com> Reported-by: James A. Peltier <jpeltier@sfu.ca> Signed-off-by: Michael Brown <mcb30@ipxe.org>
ipxe · Jul 27, 2015 · 99d3516 · 99d3516
1 parent 2b15ae5
commit 99d3516
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/core/xferbuf.c b/src/core/xferbuf.c
@@ -309,7 +309,7 @@ struct xfer_buffer * xfer_buffer ( struct interface *intf ) {
 	/* Check that this operation is provided by the same interface
 	 * which handles xfer_deliver().
 	 */
-	intf_get_dest_op ( intf, xfer_deliver, &xfer_deliver_dest );
+	( void ) intf_get_dest_op ( intf, xfer_deliver, &xfer_deliver_dest );
 
 	if ( op && ( dest == xfer_deliver_dest ) ) {
 		xferbuf = op ( object );