import from plan9
diff --git a/src/cmd/tcs/conv_gb.c b/src/cmd/tcs/conv_gb.c
index 7083525..6838b77 100644
--- a/src/cmd/tcs/conv_gb.c
+++ b/src/cmd/tcs/conv_gb.c
@@ -88,6 +88,7 @@
 	gbproc(-1, &r, nin);
 	if(r > ob)
 		OUT(out, ob, r-ob);
+	OUT(out, ob, 0);
 }
 
 void