commit af6cf586f63654f1c9d4e78b3acfafa2cfecae57
author Brad King <brad.king@kitware.com> Wed Jul 22 15:16:12 2020 -0400
committer Brad King <brad.king@kitware.com> Wed Jul 22 15:19:51 2020 -0400
tree ca82ae11bbb94f1022770a00739c4bc219d53612
parent d421274e3e11a0e6480358faa8a8e5cf48d7b3c2

cmake-gui: Fix crash when built with Qt 5.14 or later

In commit d7679f6427 (QCMakeCacheView: use non-deprecated List and Set
constructions, 2020-06-10, v3.18.0-rc2~13^2) the conversion of the
`this->properties()` value to QSet is incorrect for Qt 5.14+.  The
problem is that `this->properties()` returns by value, so the range
`this->properties().begin(), this->properties().end()` provides
iterators to two different instances.  Use an intermediate temporary
copy of the value to get a consistent iterator range.

Fixes: #20981

Source/QtDialog/QCMakeCacheView.cxx

diff --git a/Source/QtDialog/QCMakeCacheView.cxx b/Source/QtDialog/QCMakeCacheView.cxx
index b1f4a82..9b24fbd 100644
--- a/Source/QtDialog/QCMakeCacheView.cxx
+++ b/Source/QtDialog/QCMakeCacheView.cxx
@@ -226,8 +226,9 @@
 #if QT_VERSION < QT_VERSION_CHECK(5, 14, 0)
     QSet<QCMakeProperty> oldProps = this->properties().toSet();
 #else
-    QSet<QCMakeProperty> oldProps = QSet<QCMakeProperty>(
-      this->properties().begin(), this->properties().end());
+    QCMakePropertyList const& oldPropsList = this->properties();
+    QSet<QCMakeProperty> oldProps =
+      QSet<QCMakeProperty>(oldPropsList.begin(), oldPropsList.end());
 #endif
     oldProps.intersect(newProps);
     newProps.subtract(oldProps);