diff --git a/src/runtime/lfstack.go b/src/runtime/lfstack.go
index de3999a5fb..ea640eb12f 100644
--- a/src/runtime/lfstack.go
+++ b/src/runtime/lfstack.go
@@ -16,7 +16,7 @@ func lfstackpush(head *uint64, node *lfnode) {
 	node.pushcnt++
 	new := lfstackPack(node, node.pushcnt)
 	if node1, _ := lfstackUnpack(new); node1 != node {
-		println("runtime: lfstackpush invalid packing: node=", node, " cnt=", hex(node.pushcnt), " packed=", hex(new), " -> node=", node1, "\n")
+		print("runtime: lfstackpush invalid packing: node=", node, " cnt=", hex(node.pushcnt), " packed=", hex(new), " -> node=", node1, "\n")
 		throw("lfstackpush")
 	}
 	for {