qdoc: Avoid CppCodeMarker crash on abstract QML types

In a while loop, when the first QML type encountered was
abstract, qdoc didn't create a class map on the heap, but
later in the loop, the class map was used anyway. This
caused a crash because of a null pointer to the class map.

Now qdoc creates a class map if one hasn't been created
yet, even if the QML type is abstract. This might not be
correct, but the real problem is probably the order in
which qdoc processes the QML types. It should probably
always start with a non-abstract type. But this fix will
at least avoid the crash.

Task-number: QTBUG-33387
Change-Id: Icecb165261469856820f81e3866218b15416ae3b
Reviewed-by: Jerome Pasion <jerome.pasion@digia.com>

1 files changed, 7 insertions, 1 deletions

diff --git a/src/tools/qdoc/cppcodemarker.cpp b/src/tools/qdoc/cppcodemarker.cpp
index ad3c5cba47..ab58238301 100644
--- a/src/tools/qdoc/cppcodemarker.cpp
+++ b/src/tools/qdoc/cppcodemarker.cpp
@@ -1229,8 +1229,14 @@ QList<Section> CppCodeMarker::qmlSections(const QmlClassNode* qmlClassNode, Syno
                   If the QML type is abstract, do not create
                   a new entry in the list for it. Instead,
                   add its members to the current entry.
+
+                  However, if the first class is abstract,
+                  there is no current entry. In that case,
+                  create a new entry in the list anyway.
+                  I'm not sure that is correct, but it at
+                  least can prevent a crash.
                  */
-                if (!current->isAbstract()) {
+                if (!current->isAbstract() || !classMap) {
                     classMap = new ClassMap;
                     classMap->first = current;
                     all.classMapList_.append(classMap);