Fix interplay between vfork and threads
diff --git a/sysdeps/linux-gnu/trace.c b/sysdeps/linux-gnu/trace.c
index e9d47e7..ba3806d 100644
--- a/sysdeps/linux-gnu/trace.c
+++ b/sysdeps/linux-gnu/trace.c
@@ -845,7 +845,7 @@
 						  1);
 		}
 
-		continue_process(event->proc->leader->pid);
+		continue_process(event->proc->parent->pid);
 
 		/* Remove the leader that we artificially set up
 		 * earlier.  */