tst_qqmllanguage::receivers() failed in all developer builds

agent:2018/11/02 08:12:27 build.go:313: [make check -j1] 900 900
agent:2018/11/02 08:12:27 build.go:193: /home/qt/work/qt/qtdeclarative/tests/auto/qml/qqmllanguage/target_wrapper.sh  ./tst_qqmllanguage receivers
agent:2018/11/02 08:12:27 build.go:193: [     0.000 D] qt.qpa.xcb TestNamespace::QXcbBasicConnection::initializeShm - Has MIT-SHM     : true
agent:2018/11/02 08:12:27 build.go:193: [     0.000 D] qt.qpa.xcb TestNamespace::QXcbBasicConnection::initializeShm - Has MIT-SHM FD  : true
agent:2018/11/02 08:12:27 build.go:193: [     0.002 D] qt.qpa.screen TestNamespace::QXcbScreen::QXcbScreen - Failed to parse EDID data for output "default" edid data:  ""
agent:2018/11/02 08:12:27 build.go:193: [     0.004 D] qt.qpa.screen TestNamespace::QXcbConnection::initializeScreens - adding QXcbScreen(0x1024400, name="default", geometry=1280x800+0+0, availableGeometry=1213x773+67+27, devicePixelRatio=1.0, logicalDpi=QPair(96.0,96.0), physicalSize=339.0x212.0mm, screenNumber=0, virtualSize=1280x800 (1280.0x800.0mm), orientation=Qt::LandscapeOrientation, depth=24, refreshRate=76.0, root=299, windowManagerName="GNOME Shell") (Primary: true )
agent:2018/11/02 08:12:27 build.go:193: [     0.004 D] qt.qpa.screen TestNamespace::QXcbConnection::initializeScreens - primary output is "default"
agent:2018/11/02 08:12:27 build.go:193: [     0.081 D] qt.qpa.xcb TestNamespace::QXcbEventDispatcher::createEventDispatcher - using glib dispatcher
agent:2018/11/02 08:12:27 build.go:193: [     0.092 D] qt.qpa.input.methods.serialize TestNamespace::QIBusEngineDesc::deserializeFrom - QIBusEngineDesc::fromDBusArgument() "(sa{sv}ssssssssussssssss)"
agent:2018/11/02 08:12:27 build.go:193: [     0.092 D] qt.qpa.input.methods TestNamespace::QIBusPlatformInputContext::QIBusPlatformInputContext - socketWatcher.addPath "/home/qt/.config/ibus/bus/3f4251b8257548d2b54496446bfa4288-unix-0"
agent:2018/11/02 08:12:27 build.go:193: ********* Start testing of tst_qqmllanguage *********
agent:2018/11/02 08:12:27 build.go:193: Config: Using QtTest library 5.13.0, Qt 5.13.0 (x86_64-little_endian-lp64 shared (dynamic) debug build; by GCC 8.2.0)
agent:2018/11/02 08:12:27 build.go:193: PASS   : tst_qqmllanguage::initTestCase()
agent:2018/11/02 08:12:27 build.go:193: FAIL!  : tst_qqmllanguage::receivers() 'o->isSignalConnected(QMetaMethod::fromSignal(&MyReceiversTestObject::mySignal))' returned FALSE. ()
agent:2018/11/02 08:12:27 build.go:193:    Loc: [tst_qqmllanguage.cpp(3589)]
agent:2018/11/02 08:12:27 build.go:193: PASS   : tst_qqmllanguage::cleanupTestCase()
agent:2018/11/02 08:12:27 build.go:193: Totals: 2 passed, 1 failed, 0 skipped, 0 blacklisted, 5ms
agent:2018/11/02 08:12:27 build.go:193: ********* Finished testing of tst_qqmllanguage *********
agent:2018/11/02 08:12:27 build.go:193: [     0.112 D] qt.qml.gc.statistics TestNamespace::QV4::MemoryManager::dumpStats - Qml GC memory allocation statistics:
agent:2018/11/02 08:12:27 build.go:193: [     0.112 D] qt.qml.gc.statistics TestNamespace::QV4::MemoryManager::dumpStats - Total memory allocated: 0
agent:2018/11/02 08:12:27 build.go:193: [     0.112 D] qt.qml.gc.statistics TestNamespace::QV4::MemoryManager::dumpStats - Max memory used before a GC run: 0
agent:2018/11/02 08:12:27 build.go:193: [     0.112 D] qt.qml.gc.statistics TestNamespace::QV4::MemoryManager::dumpStats - Max memory used after a GC run: 0
agent:2018/11/02 08:12:27 build.go:193: [     0.112 D] qt.qml.gc.statistics TestNamespace::QV4::MemoryManager::dumpStats - Requests for different item sizes:
agent:2018/11/02 08:12:27 build.go:193: [     0.112 D] qt.qml.gc.statistics TestNamespace::QV4::MemoryManager::dumpStats -      < 32  bytes:  817
agent:2018/11/02 08:12:27 build.go:193: [     0.112 D] qt.qml.gc.statistics TestNamespace::QV4::MemoryManager::dumpStats -      < 64  bytes:  221
agent:2018/11/02 08:12:27 build.go:193: [     0.112 D] qt.qml.gc.statistics TestNamespace::QV4::MemoryManager::dumpStats -      < 96  bytes:  514
agent:2018/11/02 08:12:27 build.go:193: [     0.112 D] qt.qml.gc.statistics TestNamespace::QV4::MemoryManager::dumpStats -      < 128  bytes:  80
agent:2018/11/02 08:12:27 build.go:193: [     0.112 D] qt.qml.gc.statistics TestNamespace::QV4::MemoryManager::dumpStats -      < 160  bytes:  0
agent:2018/11/02 08:12:27 build.go:193: [     0.112 D] qt.qml.gc.statistics TestNamespace::QV4::MemoryManager::dumpStats -      < 192  bytes:  0
agent:2018/11/02 08:12:27 build.go:193: [     0.112 D] qt.qml.gc.statistics TestNamespace::QV4::MemoryManager::dumpStats -      >= 224  bytes:  64
agent:2018/11/02 08:12:27 build.go:193: [     0.113 D] qt.qpa.events.reader TestNamespace::QXcbEventQueue::~QXcbEventQueue - nodes on heap: 0
agent:2018/11/02 08:12:27 build.go:193: Makefile:332: recipe for target 'check' failed
agent:2018/11/02 08:12:27 build.go:193: make: *** [check] Error 1
agent:2018/11/02 08:12:27 build.go:237: Process finished with error: exit status 2