From 1a5ebfbe05c3401e33eb5b289766356d634fae80 Mon Sep 17 00:00:00 2001
From: David Schulz <david.schulz@theqtcompany.com>
Date: Mon, 11 Apr 2016 10:18:30 +0200
Subject: [PATCH] Editor: Fix crash when removing mark from the block data
 destructor.

The TextBlockUserData is destructed from QTextBlockData::free which
deletes the layout right before. So triggering a direct update from
within this destructor could result in a crash when the already deleted
layout is used.

Task-number: QTCREATORBUG-16046
Change-Id: Ifd1d4334ba8ef47c41e0b9ae078ceaf1112b5908
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>
---
 src/plugins/texteditor/textdocument.cpp | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/plugins/texteditor/textdocument.cpp b/src/plugins/texteditor/textdocument.cpp
index 1d1a47a8456..c1fd7545901 100644
--- a/src/plugins/texteditor/textdocument.cpp
+++ b/src/plugins/texteditor/textdocument.cpp
@@ -48,6 +48,7 @@
 #include <QScrollBar>
 #include <QStringList>
 #include <QTextCodec>
+#include <QTimer>
 
 #include <coreplugin/coreconstants.h>
 #include <coreplugin/icore.h>
@@ -852,10 +853,16 @@ void TextDocument::removeMarkFromMarksCache(TextMark *mark)
     QTC_ASSERT(documentLayout, return);
     d->m_marksCache.removeAll(mark);
 
+    auto scheduleLayoutUpdate = [documentLayout](){
+        // make sure all destructors that may directly or indirectly call this function are
+        // completed before updating.
+        QTimer::singleShot(0, documentLayout, &QPlainTextDocumentLayout::requestUpdate);
+    };
+
     if (d->m_marksCache.isEmpty()) {
         documentLayout->hasMarks = false;
         documentLayout->maxMarkWidthFactor = 1.0;
-        documentLayout->requestUpdate();
+        scheduleLayoutUpdate();
         return;
     }
 
@@ -879,7 +886,7 @@ void TextDocument::removeMarkFromMarksCache(TextMark *mark)
 
         if (maxWidthFactor != documentLayout->maxMarkWidthFactor) {
             documentLayout->maxMarkWidthFactor = maxWidthFactor;
-            documentLayout->requestUpdate();
+            scheduleLayoutUpdate();
         } else {
             documentLayout->requestExtraAreaUpdate();
         }