From cf92563721887d7aa3d9ce71acef1ed164d562df Mon Sep 17 00:00:00 2001
From: Matthias Kuhn <matthias@opengis.ch>
Date: Fri, 4 May 2018 08:56:38 +0200
Subject: [PATCH] Fix crash with uninitialized search widget

---
 src/gui/qgsattributeformrelationeditorwidget.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/gui/qgsattributeformrelationeditorwidget.cpp b/src/gui/qgsattributeformrelationeditorwidget.cpp
index a80737fad00..fed023258ae 100644
--- a/src/gui/qgsattributeformrelationeditorwidget.cpp
+++ b/src/gui/qgsattributeformrelationeditorwidget.cpp
@@ -39,5 +39,9 @@ void QgsAttributeFormRelationEditorWidget::createSearchWidgetWrappers( const Qgs
 
 QString QgsAttributeFormRelationEditorWidget::currentFilterExpression() const
 {
-  return mSearchWidget->expression();
+  QString filterExpression;
+  if ( mSearchWidget )
+    filterExpression = mSearchWidget->expression();
+
+  return filterExpression;
 }