Stop relying on QHash ordering

tst_rcc and tst_qdom rely on specific QHash orderings inside
rcc and QDom respectively (see QTBUG-25078 and QTBUG-25071).

A workaround is added to make them succeed: QDom checks for
all possible orderings, and rcc initializes the hash seed to 0
if the QT_RCC_TEST environment variable is set.

Change-Id: I5ed6b50602fceba731c797aec8dffc9cc1d6a1ce
Reviewed-by: João Abecasis <joao.abecasis@nokia.com>
Reviewed-by: Robin Burchell <robin+qt@viroteck.net>

1 files changed, 9 insertions, 0 deletions

diff --git a/src/tools/rcc/main.cpp b/src/tools/rcc/main.cpp
index 3873e74ee5..ad20b9e3ac 100644
--- a/src/tools/rcc/main.cpp
+++ b/src/tools/rcc/main.cpp
@@ -47,6 +47,8 @@
 #include <QFile>
 #include <QFileInfo>
 #include <QTextStream>
+#include <QAtomicInt>
+#include <QtGlobal>
 
 QT_BEGIN_NAMESPACE
 
@@ -254,9 +256,16 @@ int runRcc(int argc, char *argv[])
     return library.output(out, errorDevice) ? 0 : 1;
 }
 
+Q_CORE_EXPORT extern QBasicAtomicInt qt_qhash_seed; // from qhash.cpp
+
 QT_END_NAMESPACE
 
 int main(int argc, char *argv[])
 {
+    // rcc uses a QHash to store files in the resource system.
+    // we must force a certain hash order when testing or tst_rcc will fail, see QTBUG-25078
+    if (!qgetenv("QT_RCC_TEST").isEmpty() && !qt_qhash_seed.testAndSetRelaxed(-1, 0))
+        qFatal("Cannot force QHash seed for testing as requested");
+
     return QT_PREPEND_NAMESPACE(runRcc)(argc, argv);
 }