From ecfd7fd86234fe92abb3ca5bd96ff1d4b61ebfd0 Mon Sep 17 00:00:00 2001
From: anatoly-os <osokingauss@gmail.com>
Date: Tue, 24 Apr 2018 15:15:45 +0200
Subject: [PATCH] fix #271707: MusicXML export: crash when exporting hairpins

Cherry-picked changes from https://github.com/musescore/MuseScore/pull/3643
---
 mscore/exportxml.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/mscore/exportxml.cpp b/mscore/exportxml.cpp
index e8c2723f43a1..5b34ad79c819 100644
--- a/mscore/exportxml.cpp
+++ b/mscore/exportxml.cpp
@@ -351,7 +351,11 @@ static QString addPositioningAttributes(Element const* const el, bool isSpanStar
       float relativeY = 0;
       float spatium = el->spatium();
 
-      if (SLine const* const span = dynamic_cast<SLine const* const>(el)) {
+      const SLine* span = nullptr;
+      if (el->isSLine())
+            span = static_cast<const SLine*>(el);
+
+      if (span && !span->spannerSegments().isEmpty()) {
             if (isSpanStart) {
                   const auto seg = span->spannerSegments().first();
                   const auto userOff = seg->userOff();