From 2a7bef47facf145afa858c5cd70be88ca895119e Mon Sep 17 00:00:00 2001
From: Paul Davis <paul@linuxaudiosystems.com>
Date: Mon, 5 May 2025 21:51:23 -0600
Subject: [PATCH] return immediately in a non-void Signal if there are no
 handlers

This allows r.begin(() to not refer to undefined memory
---
 libs/pbd/pbd/signals.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libs/pbd/pbd/signals.h b/libs/pbd/pbd/signals.h
index 5f704b2aa0..dc6d69da67 100644
--- a/libs/pbd/pbd/signals.h
+++ b/libs/pbd/pbd/signals.h
@@ -503,6 +503,10 @@ SignalWithCombiner<Combiner, R(A...)>::operator() (A... a)
 		return;
 
 	} else {
+		if (s.empty()) {
+			return typename Combiner::result_type ();
+		}
+
 		std::vector<R,PBD::StackAllocator<R,nslots> > r;
 		slot_function_type functor;