From 0e9a3c95cb955b099e07d9bfa5808c02a66070f5 Mon Sep 17 00:00:00 2001
From: Alessandro Pasotti <elpaso@itopen.it>
Date: Tue, 28 May 2019 11:21:17 +0200
Subject: [PATCH 1/2] Fix crash when exporting layout

Fixes #29798
---
 src/core/layout/qgslayoutmultiframe.cpp | 29 ++++++++++++++-----------
 1 file changed, 16 insertions(+), 13 deletions(-)

diff --git a/src/core/layout/qgslayoutmultiframe.cpp b/src/core/layout/qgslayoutmultiframe.cpp
index 9a75be7e8ca9..7849da282ec7 100644
--- a/src/core/layout/qgslayoutmultiframe.cpp
+++ b/src/core/layout/qgslayoutmultiframe.cpp
@@ -385,20 +385,23 @@ void QgsLayoutMultiFrame::handlePageChange()
     }
   }
 
-  //page number of the last item
-  QgsLayoutFrame *lastFrame = mFrameItems.last();
-  int lastItemPage = mLayout->pageCollection()->predictPageNumberForPoint( lastFrame->pos() );
-
-  for ( int i = lastItemPage + 1; i < mLayout->pageCollection()->pageCount(); ++i )
+  if ( mFrameItems.count( ) )
   {
-    //copy last frame to current page
-    std::unique_ptr< QgsLayoutFrame > newFrame = qgis::make_unique< QgsLayoutFrame >( mLayout, this );
-
-    newFrame->attemptSetSceneRect( QRectF( lastFrame->pos().x(),
-                                           mLayout->pageCollection()->page( i )->pos().y() + lastFrame->pagePos().y(),
-                                           lastFrame->rect().width(), lastFrame->rect().height() ) );
-    lastFrame = newFrame.get();
-    addFrame( newFrame.release(), false );
+    //page number of the last item
+    QgsLayoutFrame *lastFrame = mFrameItems.last();
+    int lastItemPage = mLayout->pageCollection()->predictPageNumberForPoint( lastFrame->pos() );
+
+    for ( int i = lastItemPage + 1; i < mLayout->pageCollection()->pageCount(); ++i )
+    {
+      //copy last frame to current page
+      std::unique_ptr< QgsLayoutFrame > newFrame = qgis::make_unique< QgsLayoutFrame >( mLayout, this );
+
+      newFrame->attemptSetSceneRect( QRectF( lastFrame->pos().x(),
+                                             mLayout->pageCollection()->page( i )->pos().y() + lastFrame->pagePos().y(),
+                                             lastFrame->rect().width(), lastFrame->rect().height() ) );
+      lastFrame = newFrame.get();
+      addFrame( newFrame.release(), false );
+    }
   }
 
   recalculateFrameSizes();

From 2ecb3228760244d3c9df362673046a57a77db357 Mon Sep 17 00:00:00 2001
From: Alessandro Pasotti <elpaso@itopen.it>
Date: Tue, 28 May 2019 11:56:40 +0200
Subject: [PATCH 2/2] Update src/core/layout/qgslayoutmultiframe.cpp

---
 src/core/layout/qgslayoutmultiframe.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/core/layout/qgslayoutmultiframe.cpp b/src/core/layout/qgslayoutmultiframe.cpp
index 7849da282ec7..c3e4ced0a5dc 100644
--- a/src/core/layout/qgslayoutmultiframe.cpp
+++ b/src/core/layout/qgslayoutmultiframe.cpp
@@ -385,7 +385,7 @@ void QgsLayoutMultiFrame::handlePageChange()
     }
   }
 
-  if ( mFrameItems.count( ) )
+  if ( !mFrameItems.empty() )
   {
     //page number of the last item
     QgsLayoutFrame *lastFrame = mFrameItems.last();