From 01c1b0b0a90f82344fe0f43e57ba9c79d18989f6 Mon Sep 17 00:00:00 2001
From: Henric Jungheim <software@henric.org>
Date: Mon, 24 Jun 2019 15:11:53 -0700
Subject: [PATCH] Avoid warning about forward declaration not matching
 definition.

---
 src/ProjectHistory.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/ProjectHistory.h b/src/ProjectHistory.h
index 6e86d626e..639142fbb 100644
--- a/src/ProjectHistory.h
+++ b/src/ProjectHistory.h
@@ -14,7 +14,7 @@ Paul Licameli split from ProjectManager.h
 #include "ClientData.h"
 
 class AudacityProject;
-class UndoState;
+struct UndoState;
 enum class UndoPush : unsigned char;
 
 class ProjectHistory final